Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019
ORIGINAL ARTICLE
Combined effects of pressure, temperature, and magnetic field on the ground state of donor impurities in a GaAs/AlGaAs quantum heterostructure
Samah Abuzaid, Ayham Shaer, Mohammad Elsaid*
Department of Physics, An-Najah National University, Nablus,West Bank, Jordan
Received 09 February 2019; revised 15 July 2019; accepted 20 July 2019; available online 30 July 2019 Abstract In the present work, the exact diagonalization method had been implemented to calculate the ground state energy of shallow donor impurity located at finite distance along the growth axis in GaAs/AlGaAs heterostructure in the presence of a magnetic field taken to be along z direction. The impurity binding energy of the ground state had been calculated as a function of confining frequency and magnetic field * * strength. We found that the ground state donor binding energy (BE) calculated at Οc =2 R and Ο0 = 5.421R , decreases from BE=7.59822 R * to BE=2.85165 R * , as we change the impurity position from d=0.0 a* to d=0.5 a* , respectively .In addition, the combined effects of pressure and temperature on the binding energy, as a function of magnetic field strength and impurity position, had been shown using the effective-mass approximation. The numerical results show that the donor impurity binding energy enhances with increasing the pressure while it decreases as the temperature decreases.
Keywords: Binding Energy; Donor Impurity; Exact Diagonalization Method; Heterostructure; Magnetic Field.
How to cite this article Abuzaid S, Shaer A, Elsaid M. Combined effects of pressure, temperature, and magnetic field on the ground state of donor impurities in a GaAs/AlGaAs quantum heterostructure. Int. J. Nano Dimens., 2019; 10 (4): 375-390.
INTRODUCTION Low dimensional heterostructure have been of the impurity and the coulombic interaction studied intensively in the last decades, both between the system charge carrier and the donor theoretically and experimentally [1-3]. Quantum impurity change the heterostructure energy gap confined semiconductor systems such as quantum [6, 7]. The donor impurity binding energy had well (QW), quantum well wire (QWW), quantum been investigated from bulk to the quantum dot dots (QD) and quantum rings (QR) are important where it depends on the dimensionality of the elements in the present electronic devices. The system, shape, and the impurity position [1, 8, 9]. electrical, optical and transport properties of these Also, it is affected the heterostructure properties semiconductor heterostructure systems can be by the presence of the magnetic or electrical changed by external effects like: donor impurities fields, pressure, and temperature [9, 10]. For the near the heterostructure surface, electric field, quantum dot, the donor impurity binding energy magnetic field, pressure, and temperature [3,4]. increases continuously with decreasing the dot Moreover, the effect of the donor impurity on the radius, and the applied magnetic field strength, in properties of the heterostructure materials is very addition, it depends on the impurity position [11, interesting subject which has been investigated. 12]. Adding the donor impurity atoms change the The donor binding energy had been studied effective charge and mass of it, which alter the for the quantum well by using variation method, performance of the quantum devices and the where the ground state of donor binding energy transport properties [5]. The binding energy had been computed as a function of the impurity * Corresponding Author Email: [email protected] position and the QW width under different electric
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field strengths [13, 14]. The donor impurity (CQD). Alfonso et al. in [33] had investigated the energy for the ground and excited state of two- energy states of an electron confined in a two- dimensional heterostructure had been computed dimensional (2D) plane and bound to an off- as a function of magnetic field strength, for both plane shallow donor center in the presences of weak and strong magnetic field limit, using exact an external magnetic field by using variation and and perturbation methods [15]. Chuu et al. in Ref. numerical approaches. The effect of impurity on [16] obtained the donor impurity energy levels energy levels in double quantum rings had been analytically for both donor impurity located at considered by Khajeh Salehani et al. [34]. the quantum dots center, and for donor impurity In this work, we have investigated the combined located at the axis of the quantum-well wire. Zhu effects of pressure, temperature, magnetic field and Gu in Ref. [17] investigated the dependence strength and the impurity position on the ground of the energy transition on shallow donor impurity state binding energy of the donor impurity in states in a harmonic QD by using analytical heterostructure materials. We have computed method with the presence of the magnetic field. the ground state energy level of donor impurity The energy transition changes with the magnetic in a heterostructure by solving the donor impurity field strength, where the result shows the high Hamiltonian using exact diagonalization method. effects of magnetic fields on donor impurity The Hamiltonian theory of donor impurity energy states transition [17]. The dependence of located along the growth axis under the effect of the diamagnetic susceptibility and the binding a magnetic field, pressure and temperature had energy of the donor impurity on the pressure and been presented, followed by numerical results the temperature had been shown analytically. and discussion. The conclusion is given at the end Khordad and Fathizadeh found in their recent of the work. study the diamagnetic susceptibility increases by increasing the pressure and it decreases with THEORY increasing the temperature [18]. Peter in Ref. [19] This section describes the main parts of the 2. Theory reported the binding energy levels of shallow donor impurity formulation: i) the quantum hydrogenic impurities in a parabolic quantum dot heterostructure Hamiltonian, ii) the exact This section describes the main parts of the donor impurity formulation: i) the (QD)with pressure effect using variation approach. diagonalization method and iii) the pressure and Where, they are found that the ionization energy, temperaturequantum heterostructure effects Hamiltonian, on ii)the the exact computed diagonalization donor method and iii) the is purely pressure-dependent. Merchancano et al. impurity ground state binding energy by the pressure and temperature effects on the computed donor impurity ground state binding in Ref. [2] had also calculated the2. Theory binding energy of effective-mass approximation. The system is a the hydrogenic impurities in a spherical QD using quantumenergy by the heterostructure effective-mass approximation. confined inThe the system x-y isplane a quantum heterostructure This section describes the main parts of the donor impurity formulation: i) the the variation and perturbation approaches as a withconfined parabolic in the x-y confinement plane with parabolic potential confinement of potential confining of confining strength quantum heterostructure Hamiltonian, ii) the exact diagonalization method and1 iii) the function of pressure, QD size, and the impurity = *Ο 22 strength Ο0 , Vr( ) m0 r , and in the presence 0 position. The resultspressure of andthe temperature study effects show on thatthe computed the , donor( ) =impurity ground , and state 2 inbinding the presence of a donor impurity along the z- axis locatedππππ of a donor1 β 2 impurity2 along the z- axis located binding energy increases with increasing the 0 energy by the effective-mass approximation. Theat systemππππ distanceππππ is2 aππππ quantumππππ d,ππππ under heterostructure the influence of a uniform pressure [20]. The combined effects of pressure at distance d, under the influence of a uniform magnetic field strength, B= Γ , confined in the x-y plane with parabolic confinementmagnetic potential of fieldconfining strength, strength B= βΓA , applied along the and temperature on the binding energy of donor applied along the z -direction. A= ( , , 0) is the vector potential. ππππ π¨π¨π¨π¨ B ππππ0 impurity in a spherical, ( QD) = with the , and presence in the presence of of a donorz -direction. impurity along A= the z (-β axisyx, located ,0) is π΅π΅π΅π΅the vector potential. 1 β 2 2 2 2 βπ¦π¦π¦π¦ π₯π₯π₯π₯ the electric field or without 2 had 0 been investigated atππππ distanceππππ ππππ d, ππππunderππππ the influence of a uniform magneticTheThe field interaction interaction strength, B=between Γbetween the, electron the in the electron GaAs layer inand the the donor impurity, [5, 21]. GaAs layer and the donor impurity, located at The exact diagonalizationapplied along the zmethod -direction. A =had ( , been, 0) is thelocated vector potential.at distance d alongππππ theπ¨π¨π¨π¨ z-direction in AlGaAs barrier, is attractive coulomb π΅π΅π΅π΅ distance d along the z-direction in AlGaAs barrier, used to solve the problem of two interacting2 βπ¦π¦π¦π¦ π₯π₯π₯π₯ isinteraction attractive energy. The coulomb Hamiltonian interaction of the donor impurity energy. can be The written in an operator electrons in the QD includingThe interaction the pressure between the andelectron in the GaAs layer and the donor impurity, Hamiltonian of the donor impurity can be written temperature effects. The magnetization and form as: located at distance d along the z-direction in AlGaAsin an operatorbarrier, is attractive form as:coulomb magnetic susceptibility of confined electrons interaction energy. The Hamiltonian of the donor impurity can be written in an operator in parabolic quantum dot was considered in 1 1 1 2 form as: = + + + (1) both: experimental and theoretical studies 2 2 4 4 2 | | [22, 23]. Very recently, Elsaid et al. [24-32], has β1β2 ππππ 1β2 ππππ 2 2 ππππππππ ππππ π»π»π»π»οΏ½ β οΏ½ππππ 2 ππππ 2 οΏ½ 2 οΏ½οΏ½ Ο Ο β ππππ β 1 1 1 ππππππππ 2 ππππ ππππ ππππ (1) ππππππππ ππππ β ππππ studied the electronic,= thermodynamic+ and+ + in Eq. (1) can be separated into (1) two parts as: 2 2 4 4 2 | | magnetic properties of βtwo1β2 ππππ electrons1β2 ππππ confined 2 2 ππππππππ ππππ π»π»π»π»οΏ½ β οΏ½ππππ 2 ππππ 2 οΏ½ 2 οΏ½οΏ½ π»π»π»π»οΏ½ Ο Ο β ππππ β in a single quantum and coupledππππ ππππ quantumππππ dotsππππππππ ππππππππ ππππ β ππππ = + ( ) (2) in Eq. (1) can be separated into two parts as: HΛ in Eq. (1) can be separated into two parts as: β₯ οΏ½ where: Δ€ Δ€ ππππ ππππ π»π»π»π» = + ( ) (2)
376 where: Δ€ Δ€β₯ ππππ ππππ Int. J. Nano Dimens., 101 (4): 375-390,1 Autumn1 2019 = + + + (3) 2 2 4 4 2 1 1 1 β1β2 ππππ 1β2 ππππ 2 2 ππππππππ ππππ = + + β₯+ 2 (3) 2 2 2 2 4 Δ€ 4 β οΏ½ππππ 2 ππππ οΏ½ οΏ½οΏ½ Ο Ο β ππππ β1β2 ππππ 1β2 ππππ and, 2 2 ππππππππππππππππππππ ππππ ππππππππ ππππππππ Δ€β₯ β οΏ½ππππ 2 ππππ 2 οΏ½ 2 οΏ½οΏ½ Ο Ο β ππππ and, ππππππππ ππππ ππππππππ ππππππππ
Ω₯ Ω₯
2. Theory 2. Theory This section describes the main parts of the donor impurity formulation: i) the 2. Theory This section describes the main parts of the donor impurity formulation: i) the quantum heterostructure Hamiltonian, ii) the exact diagonalization method and iii) the This section describesquantum heterostructurethe main parts Hamiltonian,of the donor ii) impurity the exact formulation: diagonalization i) t hemethod and iii) the pressure and temperature effects on the computed donor impurity ground state binding quantum heterostructurepressure Hamiltonian, and temperature ii) the effects exact ondiagonalization the computed methoddonor impurity and iii) theground state binding energy by the effective-mass approximation. The system is a quantum heterostructure pressure and temperatureenergy byeffects the effectiveon the computed-mass approximation. donor impurity The ground system state is a binding quantum heterostructure confined in the x-y plane with parabolic confinement potential of confining strength confined in the x-y plane with parabolic confinement potential of confining strength energy by the effective-mass approximation. The system is a quantum heterostructure 0 ( ) = ππππ , , and in the presence of a donor0 impurity along the z- axis located confined in the x-y, plane( ) = with parabolic , and confinement in the presence potential of1 aof donorβ confining2 2 impurity strength along the z- axis locatedππππ 0 1 β 2 2 ππππ ππππ 2 ππππ ππππ ππππ at distance d, under the influence 0of a uniform magnetic field strength, B= Γ , 2 0 ππππ , ( ) = atππππ , distanceandππππ in ππππ thed, ππππ underpresenceππππ the ofinfluence a donor ofimpurity a uniform along magnetic the z- axis field located strength, B= Γ , 1 β 2 2 applied along the z -direction. A= ( , , 0) is the vector potential. ππππ π¨π¨π¨π¨ ππππ ππππ 2 ππππ ππππ0ππππ at distance d, underapplied the influence along the ofz - direction.a uniform A =magnetic ( , ,field0) is thestrength, vector B=potential.Γ π΅π΅π΅π΅ , ππππ π¨π¨π¨π¨ π΅π΅π΅π΅ 2 βπ¦π¦π¦π¦ π₯π₯π₯π₯ applied along the z -direction. A= ( , , 0) is the2 vectorβπ¦π¦π¦π¦ π₯π₯π₯π₯potential.The interaction betweenππππ π¨π¨π¨π¨the electron in the GaAs layer and the donor impurity, The interactionπ΅π΅π΅π΅ between the electron in the GaAs layer and the donor impurity, 2 βπ¦π¦π¦π¦ π₯π₯π₯π₯ located at distance d along the z-direction in AlGaAs barrier, is attractive coulomb The interactionlocated between at distance the electron d along in thethe zGaAs-direction layer inand AlGaAs the donor barrier impurity, is attractive, coulomb interaction energy. The Hamiltonian of the donor impurity can be written in an operator located at distanceinteraction d along energythe z-direction. The Hamiltonian in AlGaAs of thebarrier donor, is impurityattractive can coulomb be written in an operator form as: interaction energyform. The asHamiltonian: of the donor impurity can be written in an operator 2 2 form as: 1 (1) = 1 = 2 (4) = + + + | | + (1) 1 1 1 2 2 42 4 2 | | = + + β+ β ππππ ππππ β (1) β ππππ 2 2 2 2 β1 2 ππππ 1 2 ππππ ππππ β2ππππ2 ππππ ππππ οΏ½ 4 The4 2potential (22ππππ) represents2 | the c|oulomb interactionοΏ½ betweenππππ ππππ the electron in the GaAs β1β2 ππππ 1β12 1π»π»π»π»ππππ β οΏ½ππππ 2ππππ 2 2 ππππ οΏ½ππππ οΏ½οΏ½ ΟS.Ο Abuzaidβ ππππ et al. β = π»π»π»π»οΏ½ β οΏ½+ππππ 2 ππππ+ +2 οΏ½ in2 Eq. (1οΏ½)οΏ½ can ππππbeππππΟ separatedΟ β ππππ intoππππ (1 twoππππ) ππππβ parts as: ππππππππ ππππ β ππππ 2 ππππππππ2 4 ππππ 4ππππππππ 2 layer and| the impurityππππ| ππππ ππππππππ ion, ππππlocatedβ ππππ at distance d along the z-direction in AlGaAs barrier β1β2 ππππ in 1Eq.β2 (1) can beππππ separated into two2 parts2 as:ππππ ππππ ππππ by the dielectric constant of GaAs medium. The π»π»π»π»οΏ½ β οΏ½ππππ 2 ππππ 2 οΏ½ 2 οΏ½οΏ½ π»π»π»π»οΏ½Ο Ο β ππππ β = + ( ) (2) ππππππππ ππππ ππππππππ ππππscreenedππππ ππππ byβ theππππ dielectric constant of GaAs medium. TheHamiltonian Hamiltonian is aa harmonic harmonic oscillator type with in Eq. (1) can beπ»π»π»π»οΏ½ separated into two parts as: = + ( ) (2) (2) well-known solution.β₯ The effective confinement where: oscillator type with Δ€well - known Δ€ β₯ solution. ππππ ππππ The effective confinement Δ€frequency, is a π»π»π»π»οΏ½ where: where: = + ( )Δ€ Δ€ β₯ ππππ ππππ (2) frequency, is a combination of the magnetic combination of the magnetic field cyclotron frequency and parabolic confining 1 1 1 field cyclotron frequency and parabolic confining β₯ Ο 2 where: Δ€ Δ€ ππππ ππππ1 = 1 1 + + + (3) ΟΟ22= + c frequency,2 given as: = 2 + 4. Generally4 , there isfrequency, no 2analytical givensolution2 as: available 0 24 . Generally, there is = + + β + β 2(3) ππππ ( ) = = (4) 2 2 β1 2 ππππ 1 2 ππππ ππππππππ 2 2 ππππ ππππ β₯ 4 42 222 2 no analytical| solution| available+ for the complete β11β2 1β21 Δ€ 1 β οΏ½ππππ ππππ2 2 πππποΏ½ 0 4 οΏ½οΏ½ Ο Ο β ππππ ππππ ππππ for the complete donorππππππππ impurityππππππππ Hamiltonian. In this work, we will use the exact = β₯ + 2 + +2 2 ππππππππ (3)ππππ ππππππππ donorππππ impurityππππ β Hamiltonian.2 In 2this work, we will Δ€ 2 β οΏ½ππππ 2ππππ andοΏ½, οΏ½οΏ½ Ο Ο β ππππ (3) ππππ ππππ ππππ β ππππ β ππππππππ 4 ππππ 4ππππππππ 2ππππ ππππππππ The potential ( ) represents the coulomb interactionοΏ½ betweenππππ ππππ the electron in the GaAs β1βa2ndππππ, 1β2 ππππ 2 2 diagππππ onalizationππππ technique to solve the donor impurity Hamiltonianuse the exact given by diagonalization Eq. (1) and technique to solve Δ€β₯ β οΏ½ππππ 2 ππππ 2 οΏ½ 2 οΏ½οΏ½ Ο Ο β ππππ ππππππππ ππππ ππππππππ and, ππππππππ layer and the impurityππππ ππππ the ion, donorlocated at impurity distance d along Hamiltonian the z-direction given in AlGaAs by Eq. barrier (1) and, study its electronic properties. and study its electronic properties. screened by the dielectric constant of GaAs medium. The Hamiltonian is a harmonic 2 For zero donor2 impurity case , Eq. (1) reducesFor to harmonic zero donoroscillator impuritytype case , Eq. (1) Ω₯ (4) = = ( ) reduces to harmonic oscillator type withβ₯ a well- | with a| well-known eigenstates+ |n,m> oscillator and β₯ typeeigenener (4) withgies well. -Theknown adopted solution. basis The (|n,m> effective = confinement Δ€frequency, is a known eigenstates |n,m> and eigenenergies. The Ω₯ Δ€ β , ( , ) ) are harmonic2 2 oscillator type wave functions that have been used to ππππ ππππ ππππ β ππππ β combination of the magnetic field cyclotron frequency=Ο ΟΟ,and parabolic confining adopted basis (|n,m> nm, ( ) ) are harmonic Ω₯ ( V (Ο The potential ( ) representsThe the coulomb potentialdiagonalizeππππ interactionππππ the οΏ½ represents betweentotalππππ Hamiltonianππππ the theelectron and coulomb obtain in the the GaAs ground state energy of the impurity ππππ ππππ ππππ oscillator type wave functions that have been used interaction between the electronfrequency, in giventhe GaAs as: = + . Generally, there is no analytical solution available system. 2 to diagonalizeππππ the total Hamiltonian and obtain layer and the impurityππππ ππππ ion,layer located and at distancethe impurity d along ion, the locatedz-direction at indistance AlGaAs dbarrier 2 2 ππππ The basis wave functions are: 0 4 along the z-direction in AlGaAs barrierfor the complete screened donorππππthe impurity groundππππ Hamiltonian. state energy In this of thework, impurity we will usesystem. the exact screened by the dielectric constant of GaAs medium. The Hamiltonian| , > = is( a, harmonic) = ( ) (5) diag,onalization technique, to solve the donor impurity Hamiltonian given by Eq. (1) and 1 ππππππππππππ Δ€ππππβ₯ππππ ππππ ππππ oscillator type with well-known solution. The effective confinementππππ ππππ ππππ frequencyππππ| |ππππ | ,| isβππππ π π π π a π π π π ! ππππ| |ππππ where, , ( )= study its electronic properties. ( ) (6) 1 2 2 ( |2 |)! β2ππππ πΌπΌπΌπΌ ππππ ππππ 2πΌπΌπΌπΌ ππππ ππππ 2 2 combination of the magnetic field cyclotron frequencyππππ ππππ and parabolic confining and eigen energies π π π π ππππ ππππ ππππFor πΌπΌπΌπΌzero οΏ½donorππππ+ ππππ impurityπΏπΏπΏπΏππππ ππππcaseπΌπΌπΌπΌ , Eq. (1) reduces to harmonic oscillator type =with(2 a +well| -known| + 1) eigenstates |n,m> Δ€andβ₯ eigenenergies. The adopted basis (|n,m> = frequency, given as: = + . Generally, there is no analytical, solution available + m (7) 2 ( , ) ) are harmonic oscillatorππππππππ type wave functions that have been used to ππππππππ , 2 2 | | ππππ ππππ 2 0 where L ( ) is the standardπΈπΈπΈπΈ associatedππππ Laguerreππππ polynomialsβππππ [34]. And is an ππππ ππππ 4 diagonalizeππππ ππππ the total Hamiltonian and obtain the ground state energy of the impurity for the complete donor impurity Hamiltonian.m In 2this2 work, we willππππ useππππ ππππ the exact inverse lengthn dimension constant which is given by: ππππ πΌπΌπΌπΌ system. πΌπΌπΌπΌ m diagonalization technique to solve the donor impurity Hamiltonian givenThe basisby Eq.= wave (1) functions and are: (8) Ο Ξ± οΏ½ | , > = , ( , ) = , ( ) (5) study its electronic properties. β 1 ππππππππππππ ππππ ππππ ππππ ππππ ππππ ππππ ππππ ππππ| |ππππ | | βπππππ π π π π π π π ! ππππ| |ππππ For zero donor impurity case , Eq. (1) reduces to harmonic where, oscillator type , ( )= ( ) (6) 1 2 2 ( |2 |)! β2ππππ πΌπΌπΌπΌ ππππ ππππ 2Ω¦πΌπΌπΌπΌ ππππ ππππ 2 2 β₯ =ππππ ππππ with a well-known eigenstates |n,m> Δ€and eigenenergies. The adoptedand basiseigen energies(|n,m> π π π π ππππ ππππ ππππ πΌπΌπΌπΌ οΏ½ ππππ + ππππ πΏπΏπΏπΏππππ ππππ πΌπΌπΌπΌ ( , ) ) are harmonic oscillator type wave functions that have been used to , , = (2 + | | + 1) + m (7) Fig. 1.a ππππππππ diagonalizeππππ ππππ the total Hamiltonian and obtain the ground state energy of the| | impurity ππππ ππππ ππππ where L ( ) is the standardπΈπΈπΈπΈππππ ππππ associatedππππ Laguerreππππ polynomialsβππππ 2 [34]. And is an system. m 2 2 inverse lengthn ππππ πΌπΌπΌπΌdimension constant which is given by: πΌπΌπΌπΌ The basis wave functions are: m = (8) Ο | , > = , ( , ) = , ( ) (5) Ξ± οΏ½ β 1 ππππππππππππ ππππ ππππ ππππ ππππ ππππ ππππ ππππ ππππ| |ππππ | | βπππππ π π π π π π π ! ππππ| |ππππ where, , ( )= ( ) (6) Ω¦ !(| 2| ) 2 2 1 β2ππππ πΌπΌπΌπΌ ππππ ππππ 2πΌπΌπΌπΌ ππππ ππππ 2 2 ππππ ππππ and eigen energies π π π π ππππ ππππ ππππ πΌπΌπΌπΌ οΏ½ ππππ+ ππππ πΏπΏπΏπΏππππ ππππ πΌπΌπΌπΌ
, = (2 + | | + 1) + m (7) ππππππππ | | where L ( ) is the standardπΈπΈπΈπΈππππ ππππ associatedππππ Laguerreππππ polynomialsβππππ 2 [34]. And is an m 2 2 inverse lengthn ππππ πΌπΌπΌπΌdimension constant which is given by: πΌπΌπΌπΌ m = Fig. ( 1.b8)
Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field Ο * Figure (1) * strength (Ο )= 2 R and parabolic confinment strength Ο= 5.412 R against the number of Ξ± οΏ½ c 0 β * * basis for a) donor impurity at the origin (d = 0 a ) and b) donor impurity at (d = 0.5 a ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of
the impurity against the magnetic field strength Οc the dashed line with impurity and solid line for no impurity cases for Ο= 5.412 R * . 0 377 Ω¦ Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019 Fig. 3. The ground-state for fixed value of Ο= 2 R * against the distance for two c ** Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line).
Ω‘ Fig. 4. The ground-state binding energy against Οc , where * * * * ( Ο0 = 3.044 R for dashed line, and Ο0 = 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , and (c) d=0.5a* . * Fig. 5. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a
function of Οc and for three temperatures (5K, 100K, and 200K): ** a) Ο00= 3.044 R and b) Ο= 5.412 R . Fig. 10. The ground-state binding energy for d = 0.1 a* at constant pressure (P=10 kba and * * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line * and Ο0 = 5.412 R for the solid line). * Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Fig. 12. The variation of ground-state binding energy for d=0.1a* as a function of the pressure * ** at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K). a) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 14. The binding energy for d=0.5 a at constant pressure (P=10 kbar) and Οc = 2 R against * * temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line). Using these harmonic oscillator bases |n, m > , the matrix elements of the full donor 2 2 ( ) = = impurity Hamiltonian (4;) , ( ) , ( ) , can be diagonalized numerically to | | + obtain the desired eigenenergies.ππππ ππππ In eachππππΜ ππππ calculation step the number of basis |n, m > 2 2 οΏ½π π π π ππππ οΏ½Δ€οΏ½π π π π ππππ οΏ½ ππππ ππππ β β 2 Using2 these harmonic oscillator bases |n, m > , the matrix elements of the full donor ( ) = ππππ β=ππππ will be varied ( until4) a satisfied converging eigen energies are achieved. The stability The potential ( ) represents the |coulomb| interactionοΏ½+ betweenππππ ππππimpurity the electron Hamiltonian in the GaAs; ( ) ( ) , can be diagonalized numerically to 2 2 , , β converging procedure is displayed in Fig.1. ( ) = = 2 2 2 2 (4) ππππ ππππ ππππΜ ππππ layer and the impurityππππ ππππ ππππ ion,ππππ located ππππatβ distanceππππ β d along the z-directionobtain the in desiredAlGaAs eigenenergies. barrierοΏ½π π π π ππππ οΏ½InΔ€ οΏ½eachπ π π π calculationππππ οΏ½ step the number of basis |n, m > ( ) | | ( ) = + =οΏ½ππππ ππππ The donor impurity (4) binding energy (BE) which is defined as the difference between the The potential represents the coulomb interaction| | between+ the electron in the GaAs β will be varied until a satisfied converging eigen energies are achieved. The stability screenedππππ byππππ the dielectric constantβ ofβ 2GaAs 2medium. The Hamiltonianenergy statesis a harmonicof the Hamiltonian (Eq. 1) without the presence of the impurity (E) and layer and the impurityππππ ππππ ion,ππππ βlocatedππππ ππππ atππππ distanceππππ dβ alongππππ βthe z-direction2 2 converging in AlGaAs procedure barrier is displayed in Fig.1. The potential ( ) representsThe potential the coulomb ( ) represents interaction theοΏ½ cbetweenoulombππππ ππππ interaction the electronοΏ½ betweenππππ in theππππ the GaAs electron in the GaAs Using these harmonic oscillator bases |n, m > , the matrix elements of the full donor with itsβ₯ presence (E0). The donor impurity binding energy (BE) which( ) is defined( ) as the difference between the oscillator type with well-known solution. The effective confinement Using these Δ€frequency harmonicimpurity, oscillatoris a Hamiltonian base; s |n, , m > , ,the matrix, can be diagonalizedelements numericallyof the full to donor layer and the impurityππππscreenedππππ ion, by thelocated dielectric atππππ distanceππππ constant d along of GaAs the zmedium.-direction The in AlGaAsHamiltonian barrier is a harmonic = ππππ ππππ ππππ Μ ππππ (9) layer and the impurity ion, located at distance d along the z-directionenergy in AlGaAsstates of barrierthe Hamiltonianobtain the desired (Eq. eigenenergies. 1)οΏ½π π π π withoutππππ οΏ½InΔ€ οΏ½ eachπ π π π the calculationpresenceππππ οΏ½ step of thethe number impurity of basis (E) |n ,andm > impurity Hamiltonian; ( Using) these( )harmonic, can be diagonalizedoscillator bas numericallyes |n, m > , tothe matrix elements of the full donor combination of the magnetic field cyclotron frequency and parabolicβ₯ confiningwill be varied, until a satisf, ied converging eigen energies are achieved. The stability oscillator type with well-known solution. The effective confinementwith Δ€ frequencyits presence, (Eis 0).a 0 screened by the dielectricscreened constant by theof GaAsdielectric medium. constant The of GaAsHamiltonian medium. Theis Hamiltonian a harmonic is a harmonicconverging π΅π΅π΅π΅πΈπΈπΈπΈ procedureimpurityπΈπΈπΈπΈ βis displayed πΈπΈπΈπΈHamiltonian in Fig.1. ; ( ) ( ) , can be diagonalized numerically to obtain the desired eigenenergies.οΏ½π π π π ππππ ππππ ππππ οΏ½InΔ€οΏ½ eachπ π π π ππππΜ ππππ calculationππππ οΏ½ step the, number of, basis |n, m > The effectsThe ofdonor =the impurity pressure binding (P)energy and (BE )the which temperature is defined as the (T)difference on thebetween energy the of the = + β₯ β₯ ππππ ππππ ππππ (Μ ππππ9) combinationfrequency,oscillator of given thetype magneticas:with well -knownfield cyclotron2solution.. Generally The frequency, effectivethere is noconfinementand analytical parabolic Δ€frequency solution confining, availableis a obtain the desired eigenenergies. In each calculation step the number of basis |n, m > oscillator type with well-known solution. The effective confinement Δ€frequencywill, is bea varied until a satisfenergy iedstates converging of the Hamiltonian eigen (Eq. energies1) withoutοΏ½ π π π π the are presence achieved.ππππ οΏ½ Δ€ofοΏ½ theπ π π π impurity Theππππ stabilityοΏ½ (E) and 2 2 ππππππππ 0 ground state can be investigatedwill be0 varied using until aeffective satisfied convergingmass approximation eigen energies method are achieved. The stability combination of theππππ magneticππππ 4field cyclotron frequency andconverging parabolic procedureconfiningwith π΅π΅π΅π΅is πΈπΈπΈπΈ displayedits presenceπΈπΈπΈπΈ β (E πΈπΈπΈπΈin0). Fig.1. combination offrequency, thefor magneticthe given complete as:field donor=cyclotron impurity+ .frequency Generally Hamiltonian. , andthere parabolic isIn no this analytical work,confining wesolution willThe availableuseeffects the of exact the pressure (P) and the temperature (T) on the energy of the 2 The donor impurity binding energy converging ( BE )= which procedure is defined is displayed as the difference in F ig . (19.) between the 2 2 ππππππππ (EMA). The pressure and temperature dependence of the material electron effective frequency, given as: 0 = + . Generally, there is no analytical solution available 0 diagonalization technique to 4solve the2 donor impurity Hamiltonian given by Eq. (1) and π΅π΅π΅π΅πΈπΈπΈπΈ πΈπΈπΈπΈ β πΈπΈπΈπΈ ππππ ππππ ππππ energyground states state of thecan Hamiltonian be investigatedThe (Eq. donor 1)using without impurity effective the binding presence mass energy ofapproximation the ( BEimpurity) which (E)method is anddefined as the difference between the frequency, givenfor as:the complete= + donor. Generally impurity2 , there 2Hamiltonian. ππππis no analytical In this solution work, availablewe will use the exact The effects of the pressure (P) and the temperature (T) on the energy of the 2 0 mass, ( , ) and dielectric constant ( , ) are inserted in the impurity 2 2 ππππππππ ππππ ππππ 4 energy states of the Hamiltonian (Eq. 1) without the presence of the impurity (E) and studyfor its the electronic0 complete properties. donor impurity Hamiltonian. In this work, withwe( EMA).will its presenceuse The the βpressure exact(E0). ground and temperaturestate can be investigateddependence using of effective the material mass approximation electron effective method diagonalizationππππ ππππ technique4 to solve the donor impurity Hamiltonian given by Eq. (1) and ππππ for the complete donor impurity Hamiltonian. In this work, we will use the exactHamiltonian ππππ ππππ asππππ shown belowwith its presence (Eππππ0). ππππ ππππ (EMA).= The pressure and temperature dependence of the material electron (9) effective diagForonalization zero donor technique impurity to solve case the donor, Eq. impurity (1) reduces Hamiltonian to harmonic mass,given by Eq.(oscillator (1), ) and and type dielectric constant ( , ) are inserted in the impurity diagonalizationstudy technique its electronic to solve properties. the donor impurity Hamiltonian given by Eq. (1) and β mass, ( 1 , ) and dielectric constant ( ,= ) 1are inserted in the impurity (9) 0 ππππ study its electronic properties. β₯ = β with a well-known eigenstates |n,m> and eigenenergies. The adoptedHamiltonianππππ basisππππ asππππ shown(|n,m>( ) π΅π΅π΅π΅= belowπΈπΈπΈπΈ πΈπΈπΈπΈ β πΈπΈπΈπΈ ( )ππππ+ ππππ ππππ( )ππππ + ( , ) Δ€ Hamiltonian2ππππ (ππππ asππππ ,shown) below ππππ ππππ2 ππππ 2 0 For zero donor impurity case , Eq. (1) reduces to harmonic oscillatorThe effects type of the pressure (P) and the temperature (T) βon the energy2 2 of the study its electronic properties.( , ) ) are harmonic oscillator type wave functions that have been used to ππππ π΅π΅π΅π΅πΈπΈπΈπΈ πΈπΈπΈπΈ β πΈπΈπΈπΈ , For zero donor impurity case , Eq. (1) reduces to harmonic oscillator type 1 β 1 β 1 1 S. AbuzaidΔ€ ππππ et al. ( ) = οΏ½Theππππβ ππππ effects( )π΄π΄π΄π΄ +ofππππ the(οΏ½) pressure + ππππ( (P),ππππ) ππππandππππ theππππ temperature (T) on the energy of the with a well-known eigenstates |n,m> andβ₯ eigenenergies. The adopted basis (|n,m>( ) = = ππππ ππππ ππππ( ) + ( ππππ) + 2 ( , ) (10) ππππ ππππwith a well-known eigenstates |n,m>Δ€ andβ₯ eigenenergies. The adoptedground basis state (|n,m> can =be investigated2 (using, )2 effective2 mass2 approximation method For zero donorππππdiagonalize impurityππππ ππππ the case total Hamiltonian, Eq. (1) reduces andΔ€ obtainto harmonic the ground oscillator state typeenergy of the impurity2 ( , ) ( , ) + ππππ 2 β 2 2 Δ€ ππππ β ππππππππ οΏ½ππππβ ππππ π΄π΄π΄π΄β ππππ οΏ½ β ππππ ππππ ππππ2ππππ2ππππ , ( , ) ) (are )harmonic oscillator type wave functions that have been used to β groundππππ ππππstate ππππ can ππππbe investigated (10using) effective mass approximation method system., , ) are harmonic oscillator type wave functions that have beenΔ€ usedππππ to βοΏ½ππππβ ππππ π΄π΄π΄π΄β ππππ2 οΏ½2 2 ππππ ππππ ππππ ππππ ππππ with a well-known eigenstates |n,m> andβ₯ eigenenergies. The adopted basis (|n,m>(EMA). = The pressure and temperatureππππ dependence( , ) + of the material (10) electron effective Δ€ For quantum heterostructureππππ ππππ ππππ made2 ofππππ GaAsππππ the dielectric constant ( , ) and the diagonalizeππππ ππππ ππππ ππππthe total HamiltonianThe basis and obtainwave functionsthe ground are:state energy of the impurity For quantumππππ ππππheterostructureβππππ οΏ½ππππ 2ππππ 2 made of GaAs the ππππ Theππππ ππππ ππππdiagonalizebasisππππ waveππππ the functions total Hamiltonian are: and obtain the ground state energy of the impurity ((EMA)., ) Theππππ+ pressure and temperature dependence of the material electron effective , ( , ) ) are harmonic oscillator type wave functions that have been used to ( , ) For quantum heterostructureππππ ππππmadeππππ ππππof( οΏ½GaAsππππ , th)ππππe dielectric constant ( , ) and the mass, anddielectric dielectricβ constant constant2 2 areand inserted the electronin theππππ impurity system. system. electron effective mass ππππ( , ) are presented by [10] ππππππππ ππππ ππππππππ ππππ ππππ diagonalizeππππ ππππ the total Hamiltonian and obtain| , the> =ground state( , energy) = of the impurity( For) quantum β heterostructure electron effective ππππmademass,ππππ mass ππππof οΏ½GaAsππππ( (, ) are th,ππππ epresented) dielectric and bydielectric [10 constant] constant ( , ) and( the , ) are inserted in the impurity ππππ ππππ ππππ , , (5) effective(5) β mass β ππππ are presented by [10] The basisThe wave basis functions wave functions are: are: Hamiltonianππππ ππππ asππππ shown below ππππ ππππ ππππ 1 ππππ ππππ ππππ ππππ ππππβ ππππ ππππ system. ππππππππππππ ( , ) ππππ ππππ ππππ ππππ ππππ ππππ ππππ ππππ electron( effective) mass ( , )Hamiltonian are presentedππππ ππππ as byππππ shown [10] below ππππ ππππ ππππ ππππ| ππππ, > =ππππ , (ππππ, ππππ) = βπππππ π π π π π π π , !( )ππππ| |ππππ , (5) 12.74 exp( 1.73 Γ 10 ) exp[9.4 Γ 10 ( 75.6)] for T < 200 K | , >where, = ( , )| =| | | ( ) ππππ β1 1 The basis wave functions where, are: , ( )= , , ( ) (5) β= (6)ππππ ππππ (11) 1 2 2 1( |2 |)! ππππππππππππ 12.74( exp) =( 1ππππ13.73.18ππππΓexpππππ10( 1.73( )Γ)exp10+β3[9) exp.4( Γ[20)10.4 Γ +10β(5 ( 75(300,.6)])forT)] for T200< K200 K 1 ππππππππππππ ππππ β ππππ 2 ππππ β β2ππππ πππππΌπΌπΌπΌππππ ππππ ππππ πππππ π π π 2πΌπΌπΌπΌππππ ππππππππ ππππ β=( 2 ππππ)2ππππ 2 ( , ) β3 12β5 1 (11) ππππ ππππ ππππ ππππππππ ππππ| |ππππ | | β ππππ π π π π ππππ ! ππππ| |ππππ , 13.18 exp( 1οΏ½.73 Γ 10β3 ) exp[20( ).4=Γ 10β5 ( β 300( )])forT+2 2 ( 200) K+ ( , ) | , where,> = ππππ ππππ ( ππππ ππππ, , )( =)ππππ= ππππ ππππ ( ) βπππππ π π π π π π π ππππ ! + ππππ ππππ| (11) | ππππ ππππ ( (5) ) (6) (6) β ππππππππ 2 ππππ β1 β₯ and eigen energies, π π π π ππππ ππππ 1 | |,ππππ | |πΌπΌπΌπΌ οΏ½( |2 |)! πΏπΏπΏπΏ ππππ πΌπΌπΌπΌ β ( , ) = 1 + 7.51 2 + ( , ) β1 2 (12) 2 where, ( )= 2 2 ( 12) . 74 exp Δ€ ππππ ( 1.73β Γ 10 )βοΏ½expππππ3βππππππππ[9.4 Γ π΄π΄π΄π΄10β ππππ (οΏ½ , ) β755ππππ( ππππ.6,β))]+forππππ0.341ππππ T <ππππ200ππππ K , 1 1β2ππππ πΌπΌπΌπΌ 2πΌπΌπΌπΌ ππππ ππππ ππππ (6) β (10) β 2 2 2 2 ππππ ππππ(ππππππππππππ|2 |)! β= 2 ππππ2οΏ½ππππ ππππ ππππ ππππ ππππ Π³ Π³ 0 ππππ (11) β3 ππππ ππππ ππππ 2οΏ½ οΏ½β5ππππ β ππππ οΏ½οΏ½ ππππ ππππ ππππ ππππ ππππ β2ππππ πΌπΌπΌπΌ ππππππππ ππππ ππππ 2πΌπΌπΌπΌ ππππππππ+ ππππ ππππ ππππ 2 132 .18 exp( 1.73β Γ 10 ) expππππ [20.4Δ€Γππππ102 πΈπΈπΈπΈ ππππ(ππππ πΈπΈπΈπΈ300ππππππππππππβ1)] οΏ½forTππππβ ππππ 200π΄π΄π΄π΄ β₯βKππππ οΏ½ ππππ ππππ ππππ ππππ ππππ and eigen energies π π π π ππππ , ππππ= (2 ππππ+ |πΌπΌπΌπΌ | +οΏ½ 1) +πΏπΏπΏπΏ m ππππ πΌπΌπΌπΌ (7) ( , ) + ππππ ππππ ππππππππ ππππ ππππ andππππ eigenβπππππ π π π energiesπ π π π ! ππππ| |ππππ ( , ) = 1 + 7(.51, ) = 1.519 5.405+ Γ 10 + + β1 ( 13 ) ( 12 ) (10) | | | | ππππ+ ππππ ππππ ππππππππ β β3 ππππ ππππ ( , β)5ππππππππβ ( ππππ, ππππ+) +2042 0.341 2 ππππ where, and eigen, (energies)= π π π π ππππ ππππ ππππ πΌπΌπΌπΌ οΏ½( ) πΏπΏπΏπΏ ππππ (6)πΌπΌπΌπΌοΏ½ Π³ 2 2 β4 ππππ 2 1 2 2 ( |2 |)! β β ππππ ( , ) + | | , = (2 + | | + 1) + m 2 β (7) ππππππππ πΈπΈπΈπΈ ππππ ππππ2 οΏ½ Π³ β ππππ β1Π³ οΏ½ ππππππππππππβ₯ ππππππππ 0 L ( β2ππππ πΌπΌπΌπΌ ππππ ππππ 2πΌπΌπΌπΌ ππππ ππππ For quantum heterostructure ( ππππ )ππππ ππππ ππππmadeοΏ½ππππ ππππof οΏ½GaAsπππποΏ½ thππππe dielectricππππ constant οΏ½οΏ½ ( ππππ, ) and the where ) is theππππ standardπΈπΈπΈπΈππππ associatedππππ Laguerreππππ 2 2 polynomialsβππππ ππππππππ [34]. And is an, = 1 + 7.51 πΈπΈπΈπΈππππ +ππππ ππππ πΈπΈπΈπΈππππ βππππ ππππ β1 2 2 (12) ππππ ππππ , = (2 + | |ππππ+ 1) + m (12) (7) (7) ( , ) ( , ) + 0.341ππππ π π π π ππππ m ππππ| |2 2 ππππ πΌπΌπΌπΌ ππππ ππππ ππππ+ ππππ πΏπΏπΏπΏ ππππ πΌπΌπΌπΌ 2 β ( ,For) =quantum1.519 heterostructure5.405 Γ 10 made of+ GaAs+ th e dielectric constant (13) ( , ) and the and eigen energies where L ( ) is the standardοΏ½ associated Laguerre polynomialsππππππππ [ 34 ]. And is an Π³ Π³ ππππ 2ππππ ππππ οΏ½0 ππππππππ ππππ Ω§ inverse lengthn dimension constantπΈπΈπΈπΈ whichππππ is givenππππ by:β ππππ ππππ ππππ ππππ (οΏ½ , ) οΏ½ + 204οΏ½οΏ½ ππππ ππππ ππππ ππππ | | mππππ πΌπΌπΌπΌ electron effectiveπΌπΌπΌπΌ mass Π³ are presentedππππ byππππ [10] β4 2 2 2 ππππ ππππ m 2 πΈπΈπΈπΈ ππππ ππππ πΈπΈπΈπΈ ππππ ππππ ππππ where L inverse( lengthn) =is the( 2dimension standard+πΈπΈπΈπΈ where| constant| associated+ 1L()ππππ whichΟΞ±22 +Laguerreππππ) m is isgiven the by:polynomials β ππππ standard [ 34 associated].(7) And is an ( πΈπΈπΈπΈ,βππππ)ππππ=ππππ1.519οΏ½ 5.405β Γ 10 + οΏ½+ ππππππππ (13) ππππ ππππ (13) ππππ , ππππ πΌπΌπΌπΌ n m πΌπΌπΌπΌ electron effective mass 2( , ) are presented by [10] ππππ ππππ ππππ m ππππ + 204ππππ 2 2 =ππππ Ξ± Π³(ππππ8) ππππ ππππ β4 2 inverse lengthn dimension constantLaguerre which polynomials is given by: [34].m And is an inverse ππππ ππππβ | | πππππππππΌπΌπΌπΌππππ =2 Where ( , ) is πΌπΌπΌπΌ the free (8 electron)πΈπΈπΈπΈ ππππ ππππ mass,οΏ½ β( , ) is the pressure andοΏ½ ππππtemperatureππππ ππππππππ where L ( ) is the standardπΈπΈπΈπΈ associatedππππlength Laguerreππππ dimension polynomialsβππππ constant [34Ο]. which And is is given an by: Where is the free electron mass,ππππ ππππ ππππ( ππππ, ) is the pressure and temperature m Ξ± m οΏ½ Ο 12.74 exp( 1.73 Γ 10 )(exp,Π³ [)9.4 Γ 10 ( 75.6)] for T < 200 K Ω§ ( , ) β Where ππππis the 0free electron mass, ( m, ) ππππis the pressure and temperatureΠ³ 2 2 inverse lengthn dimension constant which is given by: = Ξ± οΏ½ dependent Where β= energy ππππ ππππ ππππ is band the free gap (electron for8) GaAsWhere mass, quantum0 Where 0πΈπΈπΈπΈis( heterostructure, theππππ is)ππππ isthe free the free pressure electron electron at Π ππππand point, mass,mass, temperature b= 1.26Γ isis the pressure (11 and) temperature ππππ πΌπΌπΌπΌ β πΌπΌπΌπΌ ( ππππβΠ³3 ) [ ( β5 ( πΈπΈπΈπΈ ππππ ππππ))] [ ( )] 13.18 expdependent1.73 energyΓ 10 bandππππ 12exp gap.74 20 forexp. 4 GaAsΓ 101 . quantum73 Γ 10 300 heterostructureexpforTΠ³ 9.4 200Γ at 10 Π K point, b=75 1.26 .6 Γfor T < 200 K (11) Ω§ Ο 0 the pressureππππ= Π³and0 temperature dependentππππ energy m dependent energyππππ band 0 gap for GaAsβ quantumπΈπΈπΈπΈβ3 βππππ heterostructureππππππππππππ ππππππππ ( at Πβ 5 point,ππππ β b=β3 1.26) ΓπΈπΈπΈπΈ [ ππππ ππππ β5 ( )] = Ξ± οΏ½ dependent 10 eV GP energy a οΏ½(8ππππand) band c = - gap3.77 forΓ 10 GaAsdependenteV quantumGPa energyπΈπΈπΈπΈ.13 heterostructure.ππππ18 ππππ bandexp gap1 .73 for at Γ GaAs Π10 point, quantum b=exp 1.26 20 heterostructureΓ.4 Γ 10 at Π300 point, forT b= 1.26200Γ K β 10(8) βeV GPbanda and gap c ππππ= -3.77 for Γ GaAs102 eVβ quantum GPa ππππ. β1 heterostructureππππ β₯ ππππ β β5 ββ11β3 β2 Ω¦ β3 β1 β1 (12) β1 + 51.οΏ½7 + 1 = ( , Ω¦ ) Ο 10 eV GPa and c = -3.77Γ 10β1 eV GPat aβ Π1 . point, b= 1.26( β, 3Γ)10 eV(β 2,GPa) + 0and.341 c = -3.77 10 eV GPa and c = -3.77Γ 10β 10eV GPeVa GP.a and c = -3.77β Γ 10 eV GPππππa . 2 ππππ β1 β₯ Ξ± οΏ½ ββ32 ( ) Usingβ these Using harmonicthese harmonicβ 1 oscillator oscillator Theβ1 baseseffective base s | nRydberg, m > β ,3 thein termmatrixΓ10β of2 eV elementspressure GPa . ofand theΠ³ temperature full donorΠ³ , is =used1 +as7 .the51 energy0 + β1 (12) β1 β1 ππππ ππππβ3ππππ β1 οΏ½ β2 β1 οΏ½ ππππ ππππ β3 β2οΏ½οΏ½ ππππ( , ) ( , ) + 0.341 of the full Rydberg donor inπΈπΈπΈπΈ termππππ ππππ of βπΈπΈπΈπΈpressureππππ ππππ and temperature is used as the energy Using these harmonic oscillator bases |n, m > , the matrix elements The effectiveΩ¦ , the matrix elements of the full donor impurity The effective Rydberg in term of pressureΠ³ and Π³ 0 impurity Hamiltonian The; effective, ( ) Rydberg, ( in) term, can ofbe pressurediagonalized( , ) =and1 . temperature519numerically5.405 isΓtoππππ 10 usedππππ ππππ as theοΏ½ energy+ οΏ½+ (13) οΏ½οΏ½ ππππ unit. The effective Rydberg in term of Thepressure effective and Rydbergtemperature in termis used+ of2042 pressureas the energy andπΈπΈπΈπΈππππ ππππtemperature ππππ πΈπΈπΈπΈππππ ππππ ππππis used as the energy impurityHamiltonian; Hamiltonian Using ;t hese ,harmonic( ) oscillator, ( ) , can bas becanes |diagonalizedn , munit.be> , the numericallymatrixtemperatureΠ³ elements to isof used the full as donor the βenergy 4 ππππ unit. 2 obtain the desired eigenenergies.ππππ ππππ In eachππππΜ ππππ calculation stepππππ the number of basis |n, m > ( , ) = 1.519 5.405 Γ 10 + + (13) ππππ οΏ½ πΈπΈπΈπΈ ππππ ππππ οΏ½ β οΏ½ ππππππππ ππππππππ + 2042 Ω¦ Using these harmonic oscillator bases |n, m > , the matrix elements of unit.the full donorοΏ½π π π π ππππ οΏ½Δ€οΏ½π π π π diagonalized numericallyππππ ππππ to ππππΜ ππππ obtain the desired unit. |n, m > Π³ ππππ β4 2 obtain the desiredimpurity eigenenergies. οΏ½Hamiltonianπ π π π ππππ οΏ½InΔ€οΏ½ eachunit.π π π π ; calculation,ππππ (οΏ½ ) step , ( the) , numbercan be diagonalized of basis numerically to ππππ ππππ ( ) ( ) eigenenergies.will be In varied each untilcalculation a satisfied step converging the number eigen energies are achieved. The stability πΈπΈπΈπΈ ππππ ππππ οΏ½ β (14) οΏ½ ππππππππ ππππππππ impurity Hamiltonian; , , will, becan varied be diagonalized until a satisf numericallyied converging to eigen energies are achieved. The( , stability) = (14) ππππ Using these harmonic oscillatorof basis base sobtain |convergingn, m >the , willdesiredthe procedure matrix be eigenenergies. varied elements isοΏ½π π π π displayedππππ ππππ untilππππ of οΏ½ InΔ€the οΏ½ ineachπ π π π full ππππFaΜ ππππ ig satisfied calculationdonor.ππππ1. οΏ½ step the number2 (of, basis)2 (|(n,,m, ))>= (14) Usingππππ ππππ these harmonic UsingππππΜ ππππ toscillatorhese harmonic bases oscillator |n, m > ,bas thee smatrix |n, m elements> , |then, mmatrix of> the elementsfull donor of the full donor β ππππ 2 ( , ) 2 ( , ) Ω§ (obtain the desired eigenenergies.οΏ½π π π π ππππ οΏ½InΔ€οΏ½ eachπ π π π calculationconvergingππππ οΏ½ step procedure the number is displayed of basis in Fig.1. ( , )π¦π¦π¦π¦= β β (14 convergingwill eigenbe varied energies until a satisf areied converging achieved. eigen The energiesπ π π π ( are,ππππ )ππππachieved.(= )2 ( The )stabilityπ΅π΅π΅π΅ ( , ) ππππ = (14) (14) impurity Hamiltonian; , ( ) ,The( )donor, can impurity be diagonalized binding numericallyenergy( , (BE) ) to which is defined 2as the, differenceππππ* ππππ ππππ,2 ππππ betweenπ¦π¦π¦π¦ππππ ππππ the β2 ( , )2 ( , ) Ω§ impurity Hamiltonianimpurity; Hamiltonian, ( ) ; , ( , )(, can) be diagonalized, ( ) , can beWhere numerically diagonalized to numerically is the effective toβ Bohr radius2 whichππππa( , PT ),givenπ π π π ( ,as:ππππ) ππππ β π΅π΅π΅π΅ will be varied until a satisfied converging eigen energies are achieved. The stability Whereπ¦π¦π¦π¦ (β ,Where) is the effectiveB β( )Bohr is radius the effective whichππππ ππππ ππππgivenππππ ππππas: ππππBohr ππππ radius The stabilitydonor impurity convergingconverging binding procedure energy ( BEis isdisplayed) whichdisplayedβ is indefined F inig .Fig.1. as 1. theπ π π π differenceππππ πππππ¦π¦π¦π¦ between theππππ β π¦π¦π¦π¦ β obtain the desired eigenenergies.ππππ ππππ In eachππππΜ energyππππ calculation statesΜ ofstep the the Hamiltonian number of basis(Eq. 1) |n without, m > the presence of the π΅π΅π΅π΅impurity (E) and π π π π ππππ ππππ obtain the desiredobtain eigenenergies. οΏ½theπ π π π οΏ½π π π π desiredππππ ππππ ππππππππ οΏ½ Ineigenenergies.Δ€οΏ½ οΏ½eachπ π π π π π π π ππππΜ οΏ½πππππ π π π calculationπππππππππππππππποΏ½πππποΏ½ οΏ½InΔ€ οΏ½eachπ π π π stepππππ ππππ calculation ππππtheWhereοΏ½ number step (of basis, the) π΅π΅π΅π΅numberis |n the, m >effective of basis | nBohr, m > radiusβπ π π π whichππππ whichππππππππ givenππππ ( ππππgiven, ππππas:) ππππas:ππππ π΅π΅π΅π΅ π΅π΅π΅π΅ converging procedure is displayed in Fig.1. The donor impurity bindingWhere energy ππππ( (BE),ππππ )ππππ is which the effective is Bohrπ΅π΅π΅π΅ Where radius whichππππ ππππ ππππgivenis ππππthe ππππas:effectiveππππ Bohr radius whichππππ ππππ ππππgivenππππ ππππas:ππππ energy states ofThe the donor Hamiltonian impurity (Eq. binding 1)β without energy the (BE presence) which of is thedefinedππππ impurityππππ ππππ as the (E) difference and ( between, ) the will bewill varied be varied until untilwill a satisfabe satisf variediedied untilconvergingconverging a satisfwith iedeigen eigen convergingits energies presence energies areeigen achieved.(Eare energies0). achieved. π΅π΅π΅π΅ The areβ stability achieved. The stability The stability β( ) The donor impurity binding energy (BE) whichdefined is defined as asthe the difference difference between betweenππππ ππππ theππππ π΅π΅π΅π΅the energy states π΅π΅π΅π΅ , = ( , ) (15) with its presence (E0). ππππ ππππ ππππ ππππ ππππ ππππ ( , ) 2 ( , ) = (15) converging procedureconverging is displayed procedure in Fisigenergy displayed.1. states in Fig of.1 .the Hamiltonian (Eq. 1) without the presence ofβ the( impurity, ) (E) and 2 converging procedure is displayedof the inHamiltonian Fig . 1 . (Eq. 1) without = the presence of π΅π΅π΅π΅ ((ππππ9,ππππ) )ππππ Δ§ ( , ) ( , ) energy states of the Hamiltonian (Eq. 1) without the presence of the impurity (E) and ( , )ππππ= ππππ ππππ β 2 β ππππ ( ππππ (,15ππππ ))Δ§ = (15) The donor impurity binding energy (BE) which is defined as the difference between the ( , )(=, ) 2 π΅π΅π΅π΅ β 2( 15 ) (15) 2 The donor impurity binding the energy impurity ( BE with) which (E) its is andpresence defined =with as (E theits0). differencepresence Finally, betweenthe (E effective ). the Rydberg can β be (9 written) as: ππππ( ,ππππ )ππππ2 ππππ ππππ ππππ ππππ ( , ) The donor impurity binding energy (BE) which is defined as the difference0 between the β ππππ ππππ ππππ Δ§ ππππβ ππππ ππππ ππππ 0 Finally, theπ΅π΅π΅π΅ effective Rydbergβ ππππ ππππcan2 ππππ beΔ§ written as: π΅π΅π΅π΅ ππππ ππππ ππππ Δ§ with its presence (E0). energy states ofenergy the Hamiltonian states of the (Eq. Hamiltonian 1) without (Eq.the presence 1) without of thetheπ΅π΅π΅π΅ presenceimpurityπΈπΈπΈπΈ πΈπΈπΈπΈ of(E)β the andπΈπΈπΈπΈ impurity (E) and ππππ ππππ πππππ΅π΅π΅π΅ β 2 ππππ ππππ ππππ β 2 energy states of the Hamiltonian (Eq. 1) without the presence Finally, 0 ofthe the effective= impurity Rydberg (E) and can be written Finally, as:ππππ theππππ ππππ ππππ effective ππππ ππππ (9ππππ) Rydberg can be written as: ππππ ππππ ππππ ππππ = β π΅π΅π΅π΅TheπΈπΈπΈπΈ effectsπΈπΈπΈπΈ β πΈπΈπΈπΈofFinally, the pressure the effective (P) andRydberg the temperature can beFinally, written (T) as:the on effective ππππthe ππππenergyππππ ππππ ofRydberg the can be written as: with =its presencewith (E 0its). presence BE (E E0 ). E 0 ( 9 ) (9) ( , ) 0 The effects of the pressure (P) and the temperature (T) on the( energy, ) = of the ( , ) (16) with its presence (E ). 0 4 β = = π΅π΅π΅π΅ πΈπΈπΈπΈ ( 9 )πΈπΈπΈπΈ β πΈπΈπΈπΈ (9) (2 , () , ) ( , ) = (16) 0 ground state can be investigated using effective β mass approximationππππ ππππ( ,ππππ )ππππ method 4 β ( , ) π΅π΅π΅π΅πΈπΈπΈπΈ πΈπΈπΈπΈ β πΈπΈπΈπΈ = The effectsThe of effects the of the pressure pressure (P) (P) and and the the temperature( , )π¦π¦π¦π¦= (T) on the energy 2 β of the 2 ( , ()16) ground state0 can be 0investigated using effective (9) mass approximationπ π π π ( ,ππππ )ππππ4= methodβ 2 ππππ( ππππ, ) ππππ = ππππ (16) (16) π΅π΅π΅π΅πΈπΈπΈπΈ πΈπΈπΈπΈ β πΈπΈπΈπΈ π΅π΅π΅π΅πΈπΈπΈπΈ πΈπΈπΈπΈ β πΈπΈπΈπΈ 2 ( , 4) β π¦π¦π¦π¦ 2 4 β (16) The effects of the pressure (P) and thetemperature temperature (T)(T) on the the energy energy of the of the ground β ππππ ππππ2 πππποΏ½(ππππππππ,ππππ )ππππ π π π π οΏ½ Δ§ππππ ππππ β 2 2( , ) (EMA). The pressure and temperature dependenceπ¦π¦π¦π¦ ofβ the materialππππ ππππ 2electronππππ ππππ effective ππππ ππππ ππππ ππππ The effects of Thethe pressureeffects of (P) 0the and pressure the temperature (P) and the (T) temperature on the energy (T) onof the energyπ π π π of theππππ ππππ π¦π¦π¦π¦ 2 2 π¦π¦π¦π¦οΏ½ππππ ππππ ππππ οΏ½ Δ§ 2 ground state can be investigated using effectiveπ π π π massππππ ππππ approximation 2 methodπ π π π ππππ ππππ 2 π΅π΅π΅π΅πΈπΈπΈπΈ(EMA).stateπΈπΈπΈπΈ β The canπΈπΈπΈπΈ pressure be investigated and temperature using dependence effective of the material mass electronοΏ½ππππ effectiveππππ ππππ οΏ½ Δ§ ground state can be investigated using effective mass approximation Tablemethod (1) shows the variation of the materialοΏ½ ππππphysicalππππ ππππ οΏ½ Δ§parameters, like effectiveοΏ½ππππ massππππ ππππ οΏ½ Δ§ groundThe effectsstate cangroundof thebe stateinvestigatedpressure can be(P) using investigatedmass,and effectivethe temperature ( using mass, )effective andapproximation (T) dielectric onmass the approximation method energyconstant ofT able the method ( (1) , shows ) Table are the inserted (1) variation shows in of the thethe impurity material variation physical of parameters the material, like effective mass approximation(EMA). Themethod pressure (EMA). and temperature The pressure dependence and of the material electron effective mass, ( , ) and dielectricβ Table constant(1) shows the( variation, ) are ofinserted the materialphysical in the physical parameters,impurity parameters like, like effective mass mass and (EMA). The pressure and temperature dependencetemperature of the dependencematerial electron ofT ableandtheeffective dielectricmaterial(1) shows constant, electronthe variation in ππππterms of oftheTable the material pressure(1) shows physical and the temperature. variationparameters of , thelike material effective physical mass parameters , like effective mass ground(EMA). state The can pressure(EMA). be and investigatedThe temperature pressureβ and usingdependenceHamiltonian temperature effectiveππππ ofππππ dependenceastheππππ shownmaterialmass below ofapproximationelectron the material effective electron method ππππeffective ππππ ππππ ππππ and dielectricdielectric constant, constant, in terms of in the terms pressure of andthe temperature. pressure and Hamiltonianeffectiveππππ ππππ asππππmass, shown mass, below( , ) andand dielectricdielectricππππ ππππconstant constantππππ ( , ) are inserted in the impurity ( , ) ( , ) ( , ) and dielectric( , ) constant, in terms of the pressureand dielectric and temperature. constant, in terms of the pressure and temperature. mass, ( , ) and mass,dielectric constantmass, and dielectric ( , andconstant ) arearedielectric insertedinserted constantβ inare thetheinsertedand impurityimpurity dielectric in are the inserted Hamiltonian impurityconstant, in the in termsimpurity oftemperature. the pressure and temperature. (EMA). Theβ pressure andβ temperature dependence of the material1 electron3. Results effective andππππ discussion1 s β Hamiltonianππππ ππππ 1ππππ (asππππ )shown=ππππ below ( ) +1 ππππ ( ππππ) ππππ 3+. Results ( ,and ) discussion s Hamiltonianππππ ππππ asππππ Hamiltonianshownππππ belowasππππππππ asshown ππππ shown belowbelow ππππ ππππ ππππ ππππ ππππ ππππ ( ) 2 Hamiltonianππππ ππππ asππππ shown below ππππ ππππ ππππ ( ) = (2 ) +3. ,Results( ) and + discussion( , sRESULTS) 2 AND DISCUSSIONS mass, ( , ) and dielectric constant ( ( , )) are inserted 3in. Resultsthe2 impurity andππππ discussion s β 3. Results2 2 and discussions 2 , β1 2 1 β 1 1 Δ€ 1ππππ For heterostructure1ππππ οΏ½ππππβ ππππ systemπ΄π΄π΄π΄ββ ππππ madeοΏ½ Forfrom2 ππππ 2 heterostructure GaAsππππ ππππ theππππ materialππππ system parameters made are: fromdielectric GaAs 1 ( ) = ( ) = ( )1+ ( ππππ) β( )+(+ ) =(( ), ππππ) +ππππ ππππβ ( ,( ) ) + Forππππ ( heterostructure) + ( system , ()10 )made from GaAs the material parameters are: dielectric Hamiltonianππππ ππππ asππππ shown2 below( , ) Δ€2 ππππ ( , )ππππ 2ππππ ππππ2 οΏ½ππππβ2ππππ2 ( 2, π΄π΄π΄π΄) ππππ οΏ½ 2 ππππ ππππ ππππ2 ππππ2ππππ ( ) = ( ) + ( ) + (ππππ, )ππππ ππππFor βheterostructure2ππππ 2 β ( system , ) 2 *made 2 + from (the10 GaAs) material the material parameters parameters are: are: dielectric dielectric constant ππππ Fig. 15ππππ. The Forbindingconstant 2heterostructure energy for= 12d=0.5.4 system,a effective against made the Rydber ΟForfromc at heterostructurefixed GaAsβ temperature= 5the.926 material2 system 2(20 K) and forparameters made threethe effective from are: GaAs massdielectric the of materialan parameters are: dielectric 2 ( , ) β 2 β2 β (β , ) + ππππ ππππ * Δ€ ππππ Δ€ ππππ οΏ½ππππβ ππππ π΄π΄π΄π΄β πππποΏ½ππππβοΏ½ ππππΔ€ ππππ2πππππ΄π΄π΄π΄2 ππππππππ οΏ½ππππβ ππππ ππππππππ οΏ½ππππππππβππππππππ ππππ ππππ 2constantπ΄π΄π΄π΄β ππππ 2οΏ½ = 12ππππ.4, **ππππ,effective effectiveππππ ππππ ππππRydber Rydber = R5.926= 5.926 meVand the and effective mass of an ππππππππ ππππ ππππ ππππ ππππππππ ππππ pressure ππππ values ππππ ( 10 )β (0, 10, and (10 20) kbar): a) for ( Ο00= 3.044 Rbβ ) and Ο= 5.412 R ). β 1 2 2 1 ππππ =ππππ 12 ππππ ππππ . 4 (10)ππππ = 5 . 926 (10) Δ€ ππππ οΏ½ππππβ ππππ π΄π΄π΄π΄β ππππ (οΏ½ , ) Forππππ +quantum(ππππ , ππππβ) ππππ heterostructureconstantππππ+ 2 ππππmade,ππππ2 effective ππππof οΏ½2GaAsππππ Rydber thππππe dielectric constant * = 12 .and4 ( the, )effective andβ the mass of= an5.926 ( ) = ( ππππ) + (Fig.) ππππ16. The+ππππ variationconstantelectron( ,of ground ) (ππππ= =12,-state0.)4.067, bindingeffective + atenergy ambientRydber forconstant d = zero0.5π π π π =a temperature 5against.926 the,ππππ effective ππππππππpressure andand thepressure. at Rydber fixedeffective The mass impurity of an is and the effective mass of an ππππ ππππ ππππ Forππππ( quantum) heterostructure Table 1 (102 )made of GaAs the dielectric constantππππ β = (0.067, ) and the π π π π ππππππππππππ 22 β, β2 2 ππππ2 ππππ2 2ππππ οΏ½ππππ ππππβ ππππ electron **β at ambient zero temperatureβ and pressure. The impurity is ( , ) + ππππ ππππ temperatureβ (20K)2 2and Ο2c = for Ο00= 3.044 R and Ο= 5.412 Rππππ . For quantum heterostructureFor ππππquantum heterostructureππππmadeππππ ππππof οΏ½electronGaAsππππ ππππππππmade thππππππππe effective dielectricππππof οΏ½GaAsππππelectron massconstantthππππe dielectric ππππ β =((0, ,.constant067)) areand presentedthe at ( 2ambient, ππππ) and by2 [thezero10π π π π β] temperatureππππ ππππ=ππππππππ 0and.067ππππ pressure.ππππ ππππ The impurityπ π π π is ππππππππππππ Δ€ ππππ β οΏ½ππππβ ππππ π΄π΄π΄π΄β ππππ οΏ½Table 1. Theππππelectronlocated dependenceππππ ππππ alongππππππππππππππππ= ofππππ 0 zthe. 067axis physical atππππ the at parameters distanceambientelectron ππππond,zero π π π π thewith temperaturepressure theππππ presence andππππππππππππ temperature. and of at apressure. uniformambient Theexternalzero impurity temperature magnetic is and pressure. The impurity is β 2 2 For quantum( heterostructure, ) β ππππmadeππππ ππππof οΏ½GaAsππππ thππππe dielectricππππ ππππ ππππ constantππππ ππππ ( , ) and the ππππelectronππππ ππππ effective massππππ are presented β ππππ (10 )by [10] ππππ located along z axis atβ the distance d, with the presence of a uniform external magnetic electron effectiveππππ electron mass effective( , ) mass are presented 2( , )by are [Table10 presented] 2. The( , byground) [10] ππππstateππππ β(m=0)ππππ energyππππ ππππ ππππ (inππππ R*) computed by the exact diagonalization method For quantum heterostructure ππππmadeππππ ππππof οΏ½GaAsππππ thππππe (dielectric, ) constant+ β located along ππππandππππ theππππz axisππππ atππππ the distanceππππ d, with the presence of a uniformππππ external magnetic 1 locatedfield (B)alongππππ along z axis the at ππππz the direction. distance locatedIn d, thewith fialong ππππrstthe steppresence z axis weππππ at haveππππof the a distanceuniformcalculated externald, withthe ground the magnetic presence state of a uniform external magnetic β electronππππβ ( , effectiveππππagainst) ππππ ππππ mass expansion ( method, ) are for presented various range by of[10 magnetic] field strengthππππ (1Ξ³ππππ=ππππ 6.75B (Tesla)). ππππβππππ ππππ ππππ ππππ2ππππ 2 ππππN field (B) along the z direction. In the first step we have calculated the ground state electron effective mass ( , ) are presented byππππ [10] ππππ ππππ ππππ β For quantum( , ) heterostructure( , ) ( ,made) of GaAs the dielectricfield( (B) constant along the ) (z direction., [) and theIn the( fi*rst step )we] have calculated the ground state ππππ ππππ ππππ οΏ½ππππππππ12.74ππππ Tableexp 3. The1.73field donoreigenenergyΓ (B)10 impurity along ground(whereexp the 9z state .m=0)4direction.Γ energy10 for the (E(InfieldR donorthe), and 75 (B)fi rstdonor.impurity6 along stepfor impurity weTthe of< haveGaAs/AlGaAsz binding200 direction. calculated K energy In heterostructure thethe figroundrst step state weas ahave calculated the ground state β = * ππππ ππππ ππππ eigenenergy (where m=0) for the donor impurity (11 of) GaAs/AlGaAs heterostructure as a 12.74 exp( 112.73.74Γ exp1012.(741)exp.exp73 Γ[(β910.41Γ.73ππππ10)ππππΓexp(10[9(BE(.475ΓR).))610exp )against] for([9 T. the4<75Γβ 200magnetic3.106) ]Kfor( Tfield< strength20075.6 K)] β for5Οc andT < various200 impurityK position (d) for =ππππππππ ππππ ππππ =ππππ =ππππ (13, .18) exp( 1.73 Γ 10 ππππ) exp [ 20 (11.4) Γ 10 ( (11) 300)] forT (11200) K electronβ effectiveππππ ππππ βmassππππ β ππππ (ππππβ, ππππ3 ) are presentedβ3 βby5 [10βeigenenergy3] β5 (whereππππ βm=0)ππππ5 ππππ for the donor eigenenergy*impurity of GaAs/AlGaAs(where m=0) for heterostructure the donor impurity as a of GaAs/AlGaAs heterostructure as a 13.18 exp( 113.73.18Γ exp1013.(181)exp.exp73 Γ[(20101.4.73Γ 10)Γexp10([20.4β300Γ) exp10eigenenergy)] forT[20( .4300200Γππππ 10(where) K] forT( m=0)200 Ο3000 =for K 3.044 ) ]theforTR ππππdonor. β 200impurity K of GaAs/AlGaAs heterostructure as a ( , ) 12.74 exp( 1.73 Γ 10 β3 ) exp[9.4 Γ 10 β(5 75.6)] for T < 200 K β β β3βππππ βππππ οΏ½β3 ππππ β5ππππ β ππππ β5ππππ β ππππ β * * 12.74 exp( 1.73 ΓοΏ½10 ) expοΏ½[9.4 οΏ½Γ 10 ( β=75ππππ.6)ππππ] forTable Tβ 43<.β The200 donor K impurityππππ energyβ5 (E(R2), and donor impurityππππ β1 binding energyβ₯ (BE(R )) against ( 11) ππππ β ππππ ππππ ππππβππππ 213ππππ.18 expππππ(β12 1.73( ,Γ)10ππππ=ββ₯1β13+)7exp.51 [20β₯.4 Γ 10+β5 ( 300)] forT 200 = K * (12) Ω¨ . theππππ magnetic+ field 2 strength ( 11 ) Ο ππππ c and(β 112 ) various impurity (12β₯) position (d) βfor1 Ο0 5.412 R ++7.51 1 =β( , )7.51 + 1 = ( , ) = β ππππ ππππ ( ) β3 378 β5 ( ) ( () , ) (β1, ) + 0.341 β1 ( , ) ( , ) + 0.341Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019 Ω¨ (exp( 1.73 Γ, 10 ) exp[20.4 Γ 10 ( 300, ( ,)])forT=, 1β+ 07200.β341.51 K β3 ππππ+ β5ππππβ1β (12 13.18 β β ( , ) ( , ) + 0.341 0 Ω¨ Π³ οΏ½ Π³ Π³ ππππ ππππ Π³ππππ 0οΏ½ οΏ½ Π³0 Π³ οΏ½οΏ½ ππππ Ω¨ β€ expβ3 ππππ( 1ππππ.73ππππΓππππ 10οΏ½ ππππβ)5expππππππππ οΏ½ππππβ[ππππ9 .οΏ½4β Γ 10ππππ οΏ½ ππππ( β 75οΏ½.ππππ6οΏ½ )]ππππfor ππππT <οΏ½200οΏ½ ππππ ππππK2 ππππ ππππ β1 12.74 β Ω¨ (ππππ πΈπΈπΈπΈ ππππ ππππ πΈπΈπΈπΈ πππππΈπΈπΈπΈππππ ππππ ππππ ( πΈπΈπΈπΈ, )ππππΠ³=ππππ 1 + 7.51Π³ πΈπΈπΈπΈ ππππ ππππ + πΈπΈπΈπΈ ππππ ππππ 0 (12 οΏ½ β= ππππ ππππ 2( , ) = 1.519( 1,5ππππ.405) =ππππΓ1ππππ10.519 οΏ½ 5.405 Γ+10οΏ½(ππππ+ ) + ππππ + (13 ) ( οΏ½ 11 οΏ½ ) ( 13ππππ) β1 β ππππ( β3 ) ππππ β[ β5 (β₯2 πΈπΈπΈπΈ),]ππππ 2ππππ= 1πΈπΈπΈπΈ.519ππππ ππππ(5.405, ) Γ 10( , ) + 0.341+ + (13) ( 13, ).18= exp1 + 7.511.73 Γ 10 + exp 20.4 Γ 10 + 204 β 300 + forT 204 (12) 200 K + 2042 Π³ Π³ ( β,4β1) =ππππ 1.519Π³β4 5.405ππππ2 Γ 10 2 + β4+ (132 ) β (ππππ , ) ππππ ( ,ππππ ) + 0.341 ππππ β Π³ 2 Π³ ππππ 0 β πΈπΈπΈπΈ ππππ ππππβ3 οΏ½ πΈπΈπΈπΈ βππππ ππππ οΏ½ β5 ππππ οΏ½ππππ ππππππππππππππππ πππποΏ½ππππ οΏ½ πππππππποΏ½ ππππππππππππ+ 204 ππππ οΏ½οΏ½ ππππ οΏ½ Π³ ππππ 0 πΈπΈπΈπΈ ππππππππ ππππ οΏ½ β4πΈπΈπΈπΈβ ππππ ππππ πΈπΈπΈπΈ ππππ ππππ 2 οΏ½ ππππππππ ππππππππ ππππ ππππ ππππ οΏ½ β οΏ½ Π³ ππππΠ³ 2 ππππ οΏ½οΏ½ ππππππππ β1 β₯ ππππ ππππ ( πΈπΈπΈπΈ,ππππ )ππππ=ππππ 1 +πΈπΈπΈπΈππππ7.51ππππ ππππ πΈπΈπΈπΈ +ππππ ππππ οΏ½ (β, ) = 1.519 5 . 405 Γ οΏ½ 10 (12ππππππππ) ππππππππ + + (13) β1 ππππ + 2042 ( , ) = 1.519 5.405 Γ 10 ( , +) +( , ) + 0 Π³ . 341 (13) β4 2 β + 2042 ππππ ππππ ππππππππ ππππππππ οΏ½ Ω§ Ω§ β Π³ β4 Π³ Π³ 2 πΈπΈπΈπΈ ππππ ππππ οΏ½ 0 ππππ ππππ ππππ οΏ½ οΏ½ππππππππ ππππ οΏ½οΏ½ ππππ ππππ Ω§ πΈπΈπΈπΈππππ ππππ ππππ οΏ½ β πΈπΈπΈπΈ ππππ οΏ½ππππ πππππππππΈπΈπΈπΈ ππππππππππππππππ Ω§ (1.519ππππ 5.405 Γ 10 + + (13 = ( , ) + 2042 Π³ β4 ππππ 2 Ω§ πΈπΈπΈπΈππππ ππππ ππππ οΏ½ β οΏ½ ππππππππ ππππππππ ππππ Ω§
Ω§
* Fig. 15. The binding energy for d=0.5a against the Οc at fixed temperature (20 K) for three ** pressure values (0, 10, and 20 kbar): a) for ( Ο00= 3.044 Rb ) and Ο= 5.412 R ). Fig. 16. The variation of ground-state bindingS. Abuzaid energy et for al. d = 0.5 a* against the pressure at fixed ** temperature (20K) and Ο2c = for Ο00= 3.044 R and Ο= 5.412 R . Table 1. The dependence of the physical parameters on the pressure and temperature. Table 2. The ground state (m=0) energy (in R*) computed by the exact diagonalization method 1 against Table expansion 2 method for various range of magnetic field strength (1Ξ³ = 6.75B (Tesla)). N Table 3. The donor impurity ground state energy (E(R*), and donor impurity binding energy * (BE(R )) against the magnetic field strength Οc and various impurity position (d) for * Ο0 = 3.044 R . Table 4. The donor impurity energy (E(R*), and donor impurity binding energy (BE(R*)) against * the magnetic field strength Οc and various impurity position (d) for Ο0 = 5.412 R .
Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * strength (Οc )= 2 R and parabolic confinment strength Ο0 = 5.412 R against the number of * * basis for a) donor impurity at the origin (d = 0 a ) and b) donor impurity at (d = 0.5 a ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of Figure (2) the impurity against the magnetic field strength Οc the dashed line with impurity and solid line * for no impurity cases for Ο0 = 5.412 R . * Fig. 3. The ground-state for fixed value of Οc = 2 R against the distance for two ** Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line).
Fig. 4. The ground-state binding energy against Οc , where * * * * ( Ο0 = 3.044 R for dashed line, and Ο0 = 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , and (c) d=0.5a* . * Fig. 5. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field function of Οc and for three temperatures (5K, 100K, and 200K): * * strength (Οc )= 2 R and parabolic confinment strength **Ο0 = 5.412 R against the number of a) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig.basis 10 . forThe a) ground donor- impuritystate binding at the energy origin for (d =d 0= 0.1a ) anda* at b) constant donor impurity pressur eat (P=10 (d = 0.5 kba a and). Fig. 2. The ground state energy* of the quantum heterostructure* for absence and presence of Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line the impurity against the magnetic field strength Οc the dashed line with impurity and solid line and Ο= 5.412 R* for the solid line). 0 * for no impurity cases for Ο0 = 5.412 R . Fig. 11. The variation of binding energy for d=0.1 a* against the Ο at fixed temperature (20K) Fig. 3. The ground-state for fixed value of Ο= 2 R * againstc the distance for two Figure c(3) ** for three pressure values (0, 10, **and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line). Fig. 12. The variation of ground- state binding energy for d=0.1a* as a function of the pressure Fig. 4. The ground-state binding* energy against Ο**c , where at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . Ω’ * * * * ( Ο0 = 3.044 R for dashed line, and *Ο0 = 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for * and (c) d=0.5a .= **= Int. J. Nano Dimens., 10 (4): 375-390,three temperatures Autumn 2019 (5K, 100K, and 200K). a) Ο00 3.044 R and b) Ο 5.412 R . 379 Fig. 5. The binding energy for d=0 a* at constant pressure (P=10 kbar) as a function of Ο for Fig. 14. The binding energy for d=0.5 a* at constant pressure (P=10 kbar) and Ο= 2 R * againstc **c three temperatures (5K, 100K, and* 200K) for (a ) Ο00= 3.044 R and b) Ο*= 5.412 R . temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line). * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a
function of Οc and for three temperatures (5K, 100K, and 200K): ** a) Ο00= 3.044 R and b) Ο= 5.412 R . Fig. 10. The ground-state binding energy for d = 0.1 a* at constant pressure (P=10 kba and * * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line * and Ο0 = 5.412 R for the solid line). * Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Fig. 12. The variation of ground-state binding energy for d=0.1a* as a function of the pressure * ** at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for Ω£ ** three temperatures (5K, 100K, and 200K). a) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 14. The binding energy for d=0.5 a at constant pressure (P=10 kbar) and Οc = 2 R against * * temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line). S. Abuzaid et al.
Fig 4.a
Fig 4.b
Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * strength (Οc )= 2 R and parabolic confinment strength Ο0 = 5.412 R against the number of basis for a) donor impurity at the origin (d = 0 a* ) and b) donor impurity at (d = 0.5 a* ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of
the impurity against the magnetic field strength Οc the dashed line with impurity and solid line * for no impurity cases for Ο0 = 5.412 R . * Fig. 3. The ground-state for fixed value of Οc = 2 R against the distance for two ** Ο00 , ( Ο= 3.044 R dashed line Figand 4 Ο.c0 = 5.412 R ) the solid line).
Fig. 4. The ground-state binding energy against Οc , where ( Ο= 3.044 R * for dashed line, and Ο= 5.412 R * for solid line ) (a) d = 0 a* , (b) d = 0.1 a* , 0 0 Figure 4 and (c) d=0.5a* . * Fig. 5. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R the effective mass of an electron mm= 0.067 e field (B) along the z direction. In the first step we with respect to the temperature for( Ο= 5.412 R * have 0 calculated the ground state eigenenergy at ambient zero temperature and pressure. The * solid line and for Ο0 = 3.044 R for the dashed line ). . impurity is located along z axis at the distance d, (where m=0)* for the donor impurity of GaAs/ Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed with the presence of a uniformtemperature external (20K) and formagnetic three different valuesAlGaAs of pressure heterostructure (0, 10, and 20 kbar) a) as a function of the Ω€ ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). 380 Fig. 9. The ground-state binding energy for d=0.1a* at constantInt. pressure J. Nano (P=10 Dimens., kbar) as a 10 (4): 375-390, Autumn 2019
function of Οc and for three temperatures (5K, 100K, and 200K): ** a) Ο00= 3.044 R and b) Ο= 5.412 R . Fig. 10. The ground-state binding energy for d = 0.1 a* at constant pressure (P=10 kba and * * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line * and Ο0 = 5.412 R for the solid line). * Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Fig. 12. The variation of ground-state binding energy for d=0.1a* as a function of the pressure * ** at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K). a) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 14. The binding energy for d=0.5 a at constant pressure (P=10 kbar) and Οc = 2 R against * * temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line). * Fig. 15. The binding energy for d=0.5a against the Οc at fixed temperature (20 K) for three ** pressure values (0, 10, and 20 kbar): a) for ( Ο00= 3.044 Rb ) and Ο= 5.412 R ). Fig. 16. The variation of ground-state binding energy for d = 0.5 a* against the pressure at fixed ** temperature (20K) and Ο2c = for Ο00= 3.044 R and Ο= 5.412 R .
Table 1. The dependence of the physicalS. Abuzaid parameters et al. on the pressure and temperature. Table 2. The ground state (m=0) energy (in R*) computed by the exact diagonalization method 1 against expansion method for various range of magnetic field strength (1Ξ³ = 6.75B (Tesla)). N Table 3. The donor impurity ground state energy (E(R*), and donor impurity binding energy * (BE(R )) against the magnetic field strength Οc and various impurity position (d) for Table 3 * Ο0 = 3.044 R . Table 4. The donor impurity energy (E(R*), and donor impurity binding energy (BE(R*)) against * the magnetic field strength Οc and various impurity position (d) for Ο0 = 5.412 R .
* Fig. 15. The binding energy for d=0.5a against the Οc at fixed temperature (20 K) for three ** pressure values (0, 10, and 20 kbar): a) for ( Ο00= 3.044 Rb ) and Ο= 5.412 R ). Fig. 16. The variation of ground-state binding energy for d = 0.5 a* against the pressure at fixed ** temperature (20K) and Ο2c = for Ο00= 3.044 R and Ο= 5.412 R . Table 1. The dependence of the physical parameters on the pressure and temperature. Table 2. The ground state (m=0) energy (in R*) computed by the exact diagonalization method 1 against expansion method for various range of magnetic field strength (1Ξ³ = 6.75B (Tesla)). N Table 3. The donor impurity ground state energy (E(R*), and donor impurity binding energy * functionfunction of the of magnetic the magnetic field fieldstrength strength with withimpurity impurity located located at the at origin the origin (d=0) (d=0) for for (BE( R )) against the magnetic field strength Οc and various impurity position (d) for * Ο= 3.044 R . ππππ ππππ functiontwo specifictwo0 of specific the values magnetic values of the fieldof confinemen the strength confinemen t ππππfrequency witht ππππfrequency impurity strength strength located = at 5the.412= origin5 .412, and(d=0) , and for= = TableTable 44 . The donor impurity energy (E(R*), and donor impurity binding energy (BE(R*)) against ππππ * β β the magnetic field strength Ο c and various impurity position (d) for Ο0 = 5.412 R . 0 0 0 0 two3.044 specific3 .R044. The Rvalues .accuracy The ofaccuracy the of confinemenour of obtained our obtainedt ππππ frequencyresults results are strengthtested are tested against Ο against= theΟ5. 412corresponding the π π π π corresponding, andπ π π π Ο ones=Ο ones β β β 0 0 3.044 R . The accuracy of our obtained results are tested againstΟ the correspondingπ π π π Ο ones producedproduced by by expansion expansion method method [35] [.T35able] .T able2 shows 2 shows the comparisonthe comparison between between the the β ππππ ππππ π΅π΅π΅π΅ producedground state by (m=0) expansion π΅π΅π΅π΅computed method energy [35 for] .T theable present 2 shows exact the diagonalization comparison between method theand ground stateππππ (m=0) computed energy for the present exact diagonalization method and π΅π΅π΅π΅ ground state (m=0) computed energy for the present exact diagonalization method and the availablethe available corresponding corresponding energy energy produced produced by expansionby expansion method. method. The comparisonThe comparison ππππ ππππ π΅π΅π΅π΅ theshows available a good corresponding agreement between energy bothproduced methods. by Toexpansion testπ΅π΅π΅π΅ the method.convergence The comparisonissue of our shows a good agreement between both methods.ππππ To test the convergence issue of our π΅π΅π΅π΅ showsexactexact diagonalizationa good diagonalization agreement technique, between technique, we both have we methods. haveplotted plotted To in testF igin .the1a F ig ,convergence1.1ab, the,1b ,computed the issuecomputed groundof our ground
exactstate stateenergiesdiagonalization energies (E) of (E) thetechnique, of donor the donor impuritywe haveimpurity Hamiltonianplotted Hamiltonian in F igagainst.1a against,1 bthe, the number thecomputed number of basis groundof basis(n) (n)
statefrom energiesfrom1 to 38 1 tofor (E) 38 frequency forof thefrequency donor = impurity 5.412= 5 . 412Hamiltonian , impurity , impurity distanceagainst distance thed= 0number d= 0and of 0.5 and basis 0.5 , and(n) , and β β β β β β o o fromat ma 1atgnetic to ma 38gnetic fieldfor frequency fieldstrength strength Ο == 2Ο 5 =.412. 2The π π π π .figures The, impurityπ π π π figures clearly distance clearly show dshow the= 0 numericalππππ the and numericalππππ 0.5 stabilityππππ ,stability andππππ in in * * function of the magnetic field strength with impurityΟ located at the origin (d=0)distance for d= 0 a and 0.5β a , and at magnetic fieldβ β magnetic field strength c with impurity located o β β at magnetic fieldstrength strength ΟΟc= Ο2 cπ π π π . The Theπ π π π π π π π figures figures clearly clearly show theshow numericalππππ the stabilityππππ in function of the magnetic field strength with impurityat locatedthe origin at the (d=0) originππππ for (d=0) two for specific valuesour ofcomputedour the computed scheme. scheme. The groundThe ground state stateapproaches approaches a limiting a limiting value value as the as number the number of of two specific values of the confinement ππππfrequency strength = 5.412 , and = β confinement frequency strength numerical stabilityc in our computed scheme. The ππππ ourbasis computed increases.β scheme. TheΟ groundπ π π π state approaches a limiting value as the number of two specific values of the confinement ππππfrequency strengthand = 53.044.412 R* , Theand accuracy= of our0 obtainedbasis increases.ground0 state approaches a limiting value as the 3.044 R . The accuracy of our obtained results are tested againstΟ the correspondingπ π π π Ο ones β number of basis increases. β results 0are tested against the0 correspondingbasis ones increases. 3.044 R . The accuracy of our obtained results are tested againstΟ the correspondingπ π π π Ο ones Fig. 2 displays the energy of the donor impurity 1 Fig.2Fig display.2 displays the senergy the energy of the of donor the donor impurity impurity energy energy as a functionas a function of the of magnetic the magnetic β produced by expansionproduced method by [ 35] .T expansionable 2 shows method the comparison [35] .Table between the ππππ energy as a function of the magnetic field strength N Fig.2 displays the energy of the donor impurity energy as a function of the magnetic produced by expansion method [35] .Table π΅π΅π΅π΅2 shows2 showsthe comparison the comparison between the between the field ground fieldstrength strength , for for , confinement confinementfor confinement frequency frequencyfrequency = 5. 412= 5R.412 . TheR . . solidThe solidplot ofplot the of the ππππ ground state (m=0) computed energy for the present exact diagonalization method and β β π΅π΅π΅π΅ state (m=0) computed energy for the present Thec solidc plot of the system indicates0 0 the absence ground state (m=0) computed energy for the present exact diagonalization method and fieldsystem strengthsystem indicates indicates Ο the, forΟ absence theconfinement absence of the of impurity, frequencythe impurity, and Ο the and=Ο dashed5 the.412 dashedR one . The indicates one solid indicates theplot presence theof thepresence exact diagonalization method and the available of the impurity, and the dashed one indicatesβ the the available corresponding energy produced by expansion method. The comparisonc 0 ππππ 1 system indicatesΟpresence the absence of the of the impurity. impurity, It isand Οclear the dashedfrom Fig. one 2 indicatesthat the presence the available corresponding energy produced by expansioncorresponding method. The energy comparison produced by expansionof theof impurity. the impurity. It is clearIt is clearfrom fromFig. 2Fig. that 2 thethat effect the effect of the of impurity the impurity is to isdecreas to decrease the e the π΅π΅π΅π΅ N the effect of the impurity is to decrease the energy shows a good agreementππππ between both methods. To test the convergence issue of our method. The comparison shows a good agreement π΅π΅π΅π΅ ofenergy theenergy impurity. of the ofof system.Itthe theis clearsystem. system. The from Thepresence Fig. The presence 2 presence thatof thedonor of effect donor ofimpurity donorof impuritythe impuritylowers impurity lowers the is to enerthe decreas gyener ofegy thethe of the shows a good agreement between both methods. To test the convergence issue of our exact diagonalizationbetween technique, both we havemethods. plotted To in test Fig .the1a , 1convergenceb, the computed groundlowers the energy of the heterostructure energy issue of our exact diagonalization technique,energyheterostructureheterostructure of the system.energy energy due The to due presenceit negativeto it negative of coulomb donor coulomb attraction.impurity attraction. lowers the energy of the exact diagonalization technique, we have plotted in Fig.1a ,1b, the computed ground due to it negative coulomb attraction. state energies (E) ofwe the havedonor plottedimpurity Hamiltonian in Fig. 1aagainst ,1b, the the number computed of basis (n) heterostructure energyThe due energy to it negative of the coulomb heterostructure attraction. shows a state energies (E) of thefunction donor ofimpurity the magnetic Hamiltonian field strength groundagainst the state with number energiesimpurity of basis located (E) (n) of at the the donor origin impurity(d=0) for significant dependence on the impurity position. = 5.412 The energyThe energy of the of heterostructurethe heterostructure shows shows a significant a significant dependence dependence on the on impuritythe impurity from 1 to 38 for frequencyHamiltonian against ,the impurity number distance of basis d= 0 (n) fromand 0.5 Increasing , and the impurity distance (d), changing the ππππ β β β from 1 to 38 for frequencytwo specific= 5. 412values of, impurity the confinemen distance1 to t 38 ππππdofrequency= for0 frequencyand strength 0.5 , and= 5.412 , andThe impurityposition. energyposition.= Increasing of Increasingthe heterostructurethe impuritythe impurity distanceshows distance a(d) significant, changing(d), changing dependence the systemthe system onfrom the from 2Dimpurity to2D 3D to 3D at magnetic field strength Ο = 2 . Theπ π π π figures clearly show the numericalππππ stabilityππππ system in from 2D to 3D (bulk), as displayed clearly in β β β β o β 0 0 at magnetic field strength3.044 Ο =R 2. The . Theaccuracyπ π π π figures of clearlyour obtained showc theresults numericalππππ are tested stabilityππππ againstΟ in the correspondingπ π π π position.(bulk),Ο ones(bulk), a sIncreasing displayed as displayed theclearly impurity clearly in F igindistance.3 .F ig For.3. (d) fixedFor, changing fixedvalues values ofthe impurity systemof impurity fromposition position2D (d),to 3D the(d), the our computed scheme. TheΟ groundπ π π π state approaches a limiting value as the number of β β c Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019 381 our computed scheme. TheΟ groundπ π π π state approaches a limiting value as the number of (bulk), as displayed clearly in Fig.3. For fixed values of impurity position (d), the produced bybasis increases.expansion method [35] .Table 2 shows the comparison between the ππππ basis increases. π΅π΅π΅π΅ ground state (m=0) computed energy for the present exact diagonalization method and Ω© Ω© Fig.2 displays the energy of the donor impurity energy as a function of the magnetic Fig.2 displays the energy of the donor impurity energy as a function of the magnetic the available corresponding energy produced by expansion method.= 5.412 TheR comparison Ω© field strength , for confinement frequencyππππ . The solid plot of the β field strength , for confinement frequency c= 5.412R . The solidπ΅π΅π΅π΅ plot of 0the shows a goodsystem agreement indicates Οbetween the absence both ofmethods. the impurity, To test and theΟ the convergence dashed one issue indicates of our the presence β c 0 system indicatesΟ the absence of the impurity, andΟ the dashed one indicates the presence exact diagonalizationof the impurity. technique, It is clear we havefrom plottedFig. 2 thatin F theig. 1aeffect ,1b , ofthe the computed impurity groundis to decreas e the of the impurity. It is clear from Fig. 2 that the effect of the impurity is to decrease the state energiesenergy (E) ofof thethe donorsystem. impurity The presence Hamiltonian of donoragainst impurity the number lowers of basisthe ener(n) gy of the energy of the system. The presence of donor impurity lowers the energy of the from 1 to 38heterostructure for frequency energy = due5.412 to it negative , impurity coulomb distance attraction. d= 0 and 0.5 , and β β β o heterostructure energy dueat ma tognetic it negative field strengthcoulomb attraction.Ο = 2 . Theπ π π π figures clearly show the numericalππππ stabilityππππ in The energy of the heterostructureβ shows a significant dependence on the impurity Οc π π π π The energy of the heterostructureour computed shows scheme. a significantThe ground dependence state approaches on the a limitingimpurity value as the number of position. Increasing the impurity distance (d), changing the system from 2D to 3D position. Increasing thebasis impurity increases. distance (d), changing the system from 2D to 3D (bulk), as displayed clearly in Fig.3. For fixed values of impurity position (d), the
(bulk), as displayed clearlyFig.2 displayin Fig.3s . the For energy fixed ofvalues the donor of impurity impurity position energy (d),as athe function of the magnetic field strength , for confinement frequency = 5.412R . The solid plot of the β c 0 Ω© system indicatesΟ the absence of the impurity, andΟ the dashed one indicates the presence
Ω© of the impurity. It is clear from Fig. 2 that the effect of the impurity is to decrease the energy of the system. The presence of donor impurity lowers the energy of the heterostructure energy due to it negative coulomb attraction.
The energy of the heterostructure shows a significant dependence on the impurity position. Increasing the impurity distance (d), changing the system from 2D to 3D
(bulk), as displayed clearly in Fig.3. For fixed values of impurity position (d), the
Ω©
S. Abuzaid et al.
Fig. 5.a
Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * strength (Οc )= 2 R and parabolic confinment strength Ο0 = 5.412 R against the number of basis for a) donor impurity at the origin (d = 0 a* ) and b) donor impurity at (d = 0.5 a* ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of
the impurity against the magnetic field strength Οc the dashed line with impurity and solid line * for no impurity cases for Ο0 = 5.412 R . * Fig. 3. The ground-state for fixed value of Οc = 2 R against the distance for two ** Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line).
Fig. 4. The ground-state binding energy against Οc , where = * = * * * ( Ο0 3.044 R for dashed line, and Ο0 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , and (c)Fig. d=0.5 5.b a* .
Fig. 5. The binding energy for d=0 a* at constant pressure (P=10 kbar) as a function of Ο for Figure 5 c ** three temperatures (5K, 100K, and 200K) for ( a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) = **= value of magnetic field Fig. Ο1.00 The 3.044 groundRb state ) Ο energy 5.412R of the. quantum heterostructure for fixedΩ₯ Fig. 8. The variation of ground-state binding energy* for d = 0 a* against the pressure at fixed * Fig. 1. The ground state energyFig. 1. ofThe the ground quantum state heterostructure energy strengthof the quantum for(Ο cfixed )= 2 heterostructurevalueR and of parabolic confinment strength magnetic for field fixed value of magneticΟ0 = 5.412 field R against the number of * * *** * * * * strengthtemperature(Ο )= 2 R and (20K) parabolic confinment strength and Οc = 2 R for ( Ο00= 3.044 ΟR= 5.412 and ΟR against= 5.412R the number ). of strength (Οc )= 2 R and parabolic confinment strength c Οbasis0 = 5.412 for a)R donoragainst impurity the number0 at the of origin (d = 0 a ) and b) donor impurity at (d = 0.5 a ). * * * basis for a) donor impurityFig.basis at 9 . the Thefor origin a)ground donor (d- =state impurity 0 a *binding) andFig. at b)the2 .energy donorThe origin ground impurityfor (d d=0.1= state0 a ata) energyand(d at = constant b)0.5 donorof a *the). pressure impurityquantum (P=10 at heterostructure (d =kbar) 0.5 aas) .a for absence and presence of Fig. 2. The ground state energyFig. 2. ofThe the ground quantumfunction state heterostructureof energy Οthec and impurityof for the three quantum for against absencetemperatures heterostructurethe and magnetic presence (5K, 100K,field for of strength absenceand 200K) Οandc: the presencedashed of line with impurity and solid line ** * the impurity against the magnetic field strength Οc the dashed line with impurity and solid line the impurity against the magnetic field strength Οc a) the dashedΟ00= 3.044 lineR with and b) Ο impurityfor and= 5.412 Rno solid impurity line . cases for Ο0 = 5.412 R . * * * * for no= impurity cases for Ο0 = 5.412 R . forFig. no 10 impurity. The ground cases-state for binding Ο0 5.412 energyFig.R 3. . The for dground = 0.1 -astate at constant for fixed pressurvalue ofe (P=10Οc = 2 kbaR against and the distance for two * * * * = ** Fig. 3. The ground-state forFig. fixed 3. The value Ο groundc = of 2 RΟ-state,= and 2 R for temperatureagainst fixed value the distance for (of ΟΟc 0 = for 2 3.044 R twoagainstR dashed line the distance for two c Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line). ****= * Ο , Ο= 3.044 R dashed line Ο00 , ( Οand= Ο 3.044 R=and 5.412 Ο dashed line 0 R 5.412 R the solidand for the solid line). Οline).0 = 5.412 R ) the solid line). 00( 0 ) Fig. 4. The ground-state binding energy against Οc , where * * * * * Fig. 11. The variationFig. 4of. Thebinding ground energy-state for binding d=0.1a energy against against the Ο cΟ atc , fixedwhere temperature (20K) Fig. 4. The ground-state binding energy ( Ο0 against= 3.044 ΟRc , for dashed line, where and Ο0 = 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , ** * * * ** * * * ( Οfor= three 3.044 pressureR for dashed line, values (0, 10, and and Ο20 =kbar) 5.412 a) Rfor for solid line Ο00= 5.412 Rb) (a) ) and for Ο d = 0 a , = (b)* 3.044 R d = 0.1 .a , ( Ο0 = 3.044 R for dashed line,0 and Ο0 = 5.412 R for solid line0 ) (a) d = 0 a , (b) d = 0.1 aand, (c) d=0.5a . * Fig. 12. The variation of ground* -state binding energy for* d=0.1a * as a function of the pressure and (c) d=0.5a Fig.. 5. Theand binding (c) d=0.5 energya . for d=0 a at constant pressure (P=10 kbar) as a function of Οc for * * ** * = = = ** Fig. 5. Theat fixed binding temperature energy for (20K) d=0 and at Ο constantc 2 R pressurefor Ο00 3.044 (P=10R kbar) and Ο as a function 5.412 R of. Οc for Fig. 5. The binding energy for d=0 a at constant pressurethree (P=10 temperatures kbar) as a function (5K, 100K, of andΟc for 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at** constant pressure (P=10** kbar) as a function of Ο for three temperatures (5K, 100K,three andtemperatures 200K) for (5K,a 100K,Ο= 3.044 and 200K)R and b) Ο for (a ) Ο00== 5.412 R 3.044 R . and b) Ο* = 5.412 Rc . * ( ) 00Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * *** three temperatures* (5K, 100K, and 200K). a) Ο= 3.044 R and b) Ο* = 5.412 R . * Fig. 6. The binding energy change for d=0 a at constant00 pressure= (P=10 kbar) and Οc = 2 R Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar)with and respect Οc to 2 Rthe temperature for( Ο0 = 5.412 R * Figure 6 * * Fig. 14. The binding energy for d=0.5 a at constant* pressure (P=10 kbar) and Ο*= 2 R against with respect to the= temperature for( Ο0 = 5.412 R c with respect to the temperature for( Ο0 5.412 R solid line and for Ο0 = 3.044 R for the dashed line ). . * * * temperature for( Ο=* 3.044 R for the dashed line and for Ο= 5.412 R solid line). * = solid line and for 0 Ο0 = 3.044 R for the dashed line ).0 . solid line and for Ο0 3.044 R for the dashFig. 7. ed line ).The variation. of ground-state binding energy for d=0a against the Οc at fixed Fig. 7. The variation of ground-state* binding energy for d=0a* against the Ο at fixed Fig. 7. The variation of ground-state binding energy for temperatured=0a against (20K) the andΟc at for fixed three different valuesc of pressure (0, 10, and 20 kbar) a) temperature (20K) and for three different values* of pressure= (0, 10,* **and 20 kbar)= a) Fig. 3. Fortemperature fixed values (20K) and forof impurity three different position values of pressure (d), (0,the 10, andR 20 kbar) to Ο 5.412Ra)00 3.044 Rb. This) Ο 5.412R energy. behavior agrees with ** ** * Ο= 3.044 Rb ) Ο= 5.412R Ο00= 3.044 . Rb ) Ο= 5.412R . energy of the donor Hamiltonian00 enhancesFig. 8 .as The the variation ofour ground expectation.-state binding energy for d = 0 a against the pressure at fixed * * * ** Fig. 8. The variation of groundFig. 8.- state The vabindingriation energy of ground for -dstate = 0 a bindingtemperature against energy the pressure(20K) for d and = 0at aΟ fixedc against= 2 R forthe (pressureΟ00= 3.044 at Rfixed and Ο = 5.412R ). ) * ** energy of the donor Hamiltonian enhances as theconfinement confinement strengthstrength ( temperature increasesincreases* (20K) from and Ο 3.044**= 2 R for ( Ο= 3.044 Furthermore,R and Ο= 5.412R we* ).have investigated the impurity temperature (20K) and Οc = 2 R for ( Ο00= 3.044 Fig.R 9c . and ΟThe ground= - 5.412Rstate00 binding ). energy for d=0.1a at constant pressure (P=10 kbar) as a Fig. 9. The ground-state binding* energy forfunction d=0.1a of* atΟ constant and for threepressure temperatures (P=10 kbar) (5K, as a 100K, and 200K): * * Fig. 9. The ground-state binding0 energy for d=0.1a at constant pressure (P=10 kbar)c as a ** from 3.044 R to 5.412R . This energy behavior agrees with our expectation.Ο function of Οc and for three temperatures (5K, 100K, and 200K): function of Οc and for three temperatures (5K, 100K, and 200K): a) Ο00= 3.044 R and b) Ο= 5.412 R . ** ** * = a) Ο=00= 3.044 R and b) Ο= 5.412 R . 382 a) Ο00 3.044 R and b) ΟFig. 5.412 R 10. The .ground -state binding energyInt. J. for Nano d = 0.1 Dimens., a at constant 10 (4): pressur 375-390,e (P=10 Autumn kba and 2019 * ** * Fig. 10. The ground-state Fig.binding 10. The energy ground for -dstate = 0.1 binding a at constant energy for pressur Οd c== 0.1e 2 R(P=10 a , andat kbaconstant temperature and pressur for (e (P=10Ο0 = kba 3.044 andR dashed line * * * * * Furthermore, we have investigated the impurity ground -state eigenenergy= (E) and Ο cthe= 2 R , and= temperature for (Ο0 = 3.044 R dashed line Οc 2 R , and temperature for (Ο0 3.044 R dashed line and Ο0 = 5.412 R for the solid line). * * * = and Ο0 = 5.412 R for the solid line). and Ο0 5.412 R for the solid line).Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) * * ** binding energy (BE) against the magnetic field strength , for specificFig. 11 values. The variation of of binding energy for d=0.1a against the Οc at fixed temperature (20K) Fig. 11. The variation of binding energy for d=0.1a againstfor three the Ο pressurec at fixed values temperature (0, 10, and (20K) 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . ** ** * for three pressure values for(0, three10, and pressure 20 kbar) values a) for (0, Ο 10,= 5.412 and 20Rb kbar) ) and for Ο a) for Ο00== 3.044 R 5.412 Rb . ) and for Ο= 3.044 R . c 0 Fig.00 12. The variation of ground-state binding energy for d=0.1a as a function of the pressure * * * ** and versus values of (d). Fig.4a ,4b,4c,4d show theFig. dependence 12.Ο The variations of ground Fig.the 12 -ground.state The variationbinding stateΟ energy of ground for -d=0.1stateat abinding fixed as a temperaturefunction energy forof thed=0.1 (20K) pressurea and as aΟ cfunction= 2 R forof the Ο00 pressure= 3.044 R and Ο= 5.412 R . * ** * *** at fixed temperature= (20K)= and Οc = 2 R for= Ο00= 3.044 R and Ο= 5.412 R . at fixed temperature (20K) and Οc 2 R for Fig.Ο00 13 3.044 . TheR binding and Ο energy 5.412 R for d=0.5. a at constant pressure (P=10 kbar) as a function of Οc for * * ** Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for binding energy (BE) on the magnetic field strength Fig. ,13 for. The different binding energy values for d=0.5 of aimpurity at constant pressurethree (P=10 temperatures kbar) as a function (5K, 100K, of Ο cand for 200K) . a) Ο00= 3.044 R and b) Ο= 5.412 R . ** *** * three temperatures (5K,= 100K, and 200K). a) Ο= 00= 3.044 R and b) Ο= 5.412 R . three temperatures (5K, 100K, and 200K). a) ΟFig.00 3.044 14. TheR binding and b) Ο energy 5.412 R for d=0.5 . a at constant pressure (P=10 kbar) and Οc = 2 R against * * c * * * * Fig. 14. The binding energyFig. for 14 d=0.5. The abinding at constant energy pressure for d=0.5 (P=10 a at kbar)constant and pressure Ο== 2 R (P=10 against kbar) and Οc = 2 R against = distances : (a) d=0 , (b) d=0.1 , and (c) d=0.5 Ο and two confinement frequencies temperature for( Ο0 c 3.044 R for the dashed line and for Ο0 5.412 R solid line). * * * * = temperature for( Ο0 = 3.044 R for the =dashed line and for Ο0 = 5.412 R solid line). β β β temperature for( Ο0 3.044 R for the dashed line and for Ο0 5.412 R solid line). ( =3.044 R* and ππππ =5.412R*)ππππ. The binding energyππππ (BE), against the magnetic field
0 0 strengthππππ , is greatly reducedππππ as the distances (d) increases as shown by Figs. 2, 3 and 4. Ω¦ In addition, the figures demonstrate that the binding energy increases as magnetic field
and the parabolic confinement strengths increase.
Οc ππππ0 In Table 3, we have listed the donor impurity energy and binding energy as a function of magnetic field strength for = 3.044 and for various values of d. β c 0 For = 3.044 and d=0 a*, theΟ bindingΟ energy increasesπ π π π as the magnetic field β 0 strengthΟ increases.π π π π This behavior persists for all d-values. However, the binding energy decreases as the impurity (d) increases. We can see a significant decrease in the binding energy as d increases from d=0.1 a* to d=0.5 a*. For example, at = 3.044 and β 0 = 2 the binding energy reduces significantly from 4.62499 ΟR* to 2.55177π π π π R*. β c ThisΟ resultπ π π π is due to the great reduction in the coulomb impurity energy (Eq. 4), as we mentioned earlier. The same qualitative behavior can also be observed in Table 4 with different quantitative behavior for = 5.412 . β Ο0 π π π π To see the effects of pressure and temperature parameters on the binding energy of the donor impurity, we have inserted the pressure and temperature dependent material
Ω‘Ω
S. Abuzaid et al.
function of the magnetic field strength with impurity located at the origin (d=0) for
ππππππππ function of the magnetic field strength with impurity located at the origin (d=0) fortwo specific values of the confinement frequency strength = 5.412 , and = β energyenergy of ofthe the donor donor Hamiltonian Hamiltonian enhances enhances as asthe the confinement0 confinement strength strength (0 ( ) )increases increases ππππ 3.044 R . The accuracy of our obtained results are tested againstΟ the correspondingπ π π π Ο ones two specific values of the confinement ππππfrequency strengthenergy of= the5energy.412 donor of , Hamiltoniantheand donor = Hamiltonian enhances as enhances the confinement as the confinement strength ( strength ) increases ( ) increases β 0 0 β fromfrom 3.044 3.044 R* R to* to5.412R 5.412R*. This*. This energy energy behavior behavior agrees agrees with with our our expectation. expectation.Ο Ο function of the magnetic field strength with0 impurity located *at the0 origin* (d=0) for 0 0 3.044 R . The accuracy of our obtained results are testedfrom againstΟ 3.044 the fromR corresponding*Fig.7.a to 3.044 5.412Rπ π π π R* .to Ο Thisones 5.412R energyproduced . This behavior by energy agreesexpansion behavior with agreesmethod our expectation. with [35 our] Ο.T expectation.able 2 showsΟ the comparison between the ππππ ππππ β two specific values of the confinement ππππfrequency strength = 5.412 , and = Furthermore,Furthermore,π΅π΅π΅π΅ we we have have investigated investigated the the impurity impurity ground ground -state -state eigenenergy eigenenergy (E) (E) and and the the produced by expansion method [35] .Table 2 shows the comparison between theground state (m=0) computed energy for the present exact diagonalization method and Furthermore,Furthermore, we have investigated we have investigatedβ the impurity the ground impurity -state ground eigenenergy -state eigenenergy (E) and the (E) and the ππππ3.044 R . Ο0 π π π π Ο0 The accuracyFig. of 1 .our The groundobtained state resultsenergy of arethe quantumtested heterostructureagainst the corresponding for fixed value of magnetic onesbindingbinding field energy energy (B (EB)E against) against the the magnetic magnetic field field strength strength , for , for specific specific values values of of π΅π΅π΅π΅ strength (Ο )= 2 R * and parabolic confinment strength Ο= 5.412 R * against the number of ground state (m=0) computedβ energy for the presentc exact diagonalizationbinding energymethod0 ( BandE)the against available the magneticcorresponding field strengthenergy produced , for specificby expansion values of method. The comparison binding energy (BE*) against the magnetic field* strength , for specific values of produced by expansionbasis method for a) donor [35 impurity] .Table at the 2 originshows (d = 0the a ) andcomparison b) donor impurity between at (d = 0.5 the a ). ππππ ΟcΟc Ο0Ο0 Fig. 2. The ground state energy of the quantum heterostructure for absence and presenceandand versus of versus values values of of(d) (d). Figc. Fig.4a.4 ,4b,4c,4da ,4b,4c,4d show show the the dependence0 dependences ofs ofth eth grounde ground state state ππππ c Ο π΅π΅π΅π΅ 0 Ο the available corresponding energy producedthe impurity by against expansion the magneticand versus method.field strength andvalues Theversus Ο ofthe comparison (d)dashedvalues. Fig line .of 4withshows a (d),4b,4c,4d impurity. Figa good .and4a showsolid,4b,4c,4d agreement line the dependenceshow Οbetween the dependence sboth of th methods.e grounds of Toth statee Ο testground the convergencestate issue of our energy of the donor Hamiltonian enhancesc as the confinement strength ( ) increases π΅π΅π΅π΅ ππππ * ground state (m=0) computed energy for thefor no present impurity casesexact for diagonalization Ο0 = 5.412 R . method bindingandbinding energy energy (B (EB)E on) on the the magnetic magnetic field field strength strength , for, for different different values values of ofimpurity impurity function of the magnetic field strength with impurity* π΅π΅π΅π΅ located* atbinding the origin energy= (d=0)* (B forE) exacton the diagonalization magnetic field 0technique,strength, we, for have different plotted values in F igof. 1aimpurity ,1b, the computed ground Fig. 3. The groundbinding-state for fixedenergy value (ofB ΟEc) on 2 R theagainst magnetic the distance field for two strength Ο for different values of impurity shows a good agreement between fromboth 3.044methods. R toTo 5.412R test the. Thisconvergence energy behavior issue of agrees our with our expectation. c c Ο , Ο= 3.044 R** dashed line and Ο= 5.412 R the solid line). Ο Ο the available correspondingππππ energy00 produced( by expansion0 method.) The comparisondistancedistance s s: (a): (a) d=0 d=0c, (b), (b) d=0.1 d=0.1, and, and (c) (c) d=0.5 d=0.5 and and two two confinement confinement frequencies frequencies two specific values of the confinement ππππfrequency strength = 5distance.412 s , and: (a) d=0= state, (b) energies d=0.1 (E), and ofΟ (c)thec d=0.5 donorΟ impurity and two Hamiltonianconfinement againstfrequencies the number of basis (n) exact diagonalization technique, we have plotted Fig.in 4F. igThedistance.1a ground ,1b-s,stateππππ the : (a)binding computed d=0 energy, against (b)ground d=0.1 Οc , where, and (c) d=0.5 and two confinementβ β frequenciesβ β β β * β* β * β * * * β * * Furthermore, ( Ο0 = 3.044 R we for dashed line, have investigated andπ΅π΅π΅π΅ Ο0 = 5.412 the Rimpurity for solid lineβ ground) (a) d =β -0state a , (b) eigenenergy( d =( 0.1= a3.044=, 3.044β (E)R R andand and ππππthe ππππ= 5.412R=5.412R)ππππ. The)ππππ. The binding binding energy energyππππ ππππ (BE (BE), against), against the the magnetic magnetic field field 0 * 0 * shows a good agreement between both methods.Ο To test* π π π π the *convergenceΟ ππππ* issue of ourππππ ππππ 3state.044 energies R . The accuracy(E) of the of donor our obtained impurity results Hamiltonian are tested against( against=3.044 the the and(number correspondingR (c) =andd=0.53.044 ofaππππ. basis=R5.412R andones (n) from )ππππ.= The5.412R 1 to binding 38 )for. The frequencyenergy bindingππππ (BE energy), against= 5 .(BE412 the), againstmagnetic , impurity the field magnetic distance fieldd= 0 and 0.5 , and Fig. 5. The binding energy for d=0 a* at constant pressure (P=10 kbar) as a function of Ο0 for0 0 0 β β β β binding energy (BE) against the magnetic field strength , forstrengthππππ specificstrengthππππc , is ,values isgreatly greatly of reducedππππ reducedππππ as asthe the distances distances (d) (d) increases increases as asshown shown by by Fig Fsig. s2,. 2,3 and3 and 4. 4. 0 0 0 **0 o exact diagonalization technique,three temperatures we have (5K, 100K,plotted and 200K)inππππ F forig . 1a(a ) Ο,1b=,3.044 the Rcomputed and b) Οππππ ground= 5.412 R . Ο = 2 π π π π ππππ ππππ producedfrom 1 to 38by for frequencyexpansion method= 5. 412[35] .T ,able impurity 2 shows distancestrengthππππ the comparisond,= is 0strength greatly and ,betweenreduced 0.5ππππis00 greatly , asandthe reducedtheat madistancesgnetic as the field(d) distances increases strength (d) as increases shown by. asThe Fshownig figuress. 2, by3 clearly andFig s4. . 2, show 3 and the 4 .numerical stability in * c * 0 ππππ Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar)Ο and Οc = 2 R Ο β and versusβ values of (d). Fig.4a β,4b,4c,4d showβ the dependenceIns Inaddition, of addition, the ground the the figuresc figuresstate demonstrate demonstrate that that the the binding binding energy energy increases increases as asmagnetic magnetic field field state energieso (E) of the donor impurity Hamiltonian against the number *of basis (n) π΅π΅π΅π΅ with respect to theIn temperature addition, for( theΟ 0figures= 5.412 ourR demonstrate computed scheme. that the ThebindingΟ ground energyπ π π π state increases approaches as magnetica limiting field value as the number of at magnetic field strength Ο = 2 . Theπ π π π figures clearlyIn show addition, the numericalππππ theFig.7.b figures stabilityππππ demonstrate in that the binding energy increases as magnetic field ground state (m=0) computed energy for the present solid line and for exact diagonalizationΟ= 3.044 R *method for the dash anded line ). . bindingβ energy (BE) on the magnetic0 field strength , for different and values and the the parabolicof parabolic impurity confinement confinement strength strengths s increase. increase. from 1 to 38 for frequency = 5.412 , impurity distance d= 0 * and 0.5 , and c Fig. 7. The variation of ground-state bindingFigure energy 7 for d=0a against the Οc at fixed our computed scheme. TheΟ groundπ π π π state approaches a limiting and valuethe parabolic asand the the numberconfinement parabolic ofbasis confinement strength increases.s strength increase.s increase. the available corresponding energy producedtemperature by expansion (20K) andβ for threemethod. different The values comparison of pressureβ (0, c10, and 20β kbar) a)c c 0 0 o Ο Ο Ο ππππ ππππ distances : (a) d=0 , (b) d=0.1 c **, and (c) d=0.5 and two confinement frequencies0 at magnetic field strength Ο = 2 ππππ . Theπ π π π figuresc Ο00= 3.044 clearlyRb show ) Ο= 5.412Rthe numericalππππ. stabilityππππ in0 Οβ Ο β β ππππ In InTable Tableππππ 3, 3we, we have have listed listed the the donor donor impurity impurity energy energy and and binding binding energy energy as asa a basis increases. π΅π΅π΅π΅ * Fig. 8. The variation* β of ground-state binding * energyIn forTable d = 0 a3 ,against weFig havethe.2 displaypressure listed ats fixedthethe donorenergy impurity of the donor energy impurity and binding energy energy as a functionas a of the magnetic shows a good agreement between both methods. To testππππ the convergenceIn Tableππππ* 3, issuewe have of** ourlistedππππ the donor impurity energy and binding energy as a ( =3.044c temperature R and (20K)= and5.412R Ο= 2 R). forThe ( Ο binding= 3.044 R energy and Ο (BE= 5.412R), against ). the magnetic field our computed scheme. TheΟ groundπ π π π state approachesc a limiting00 value as the number of * functionfunction of ofmagnetic magnetic field field strength strength for for = =3.0443.044 and and for for various various values values of ofd. d. 0 Fig. 9. The ground-state0 binding energy for d=0.1a at constant pressure (P=10 kbar) as a = 5.412R exact diagonalizationground technique, -state eigenenergy we have plotted (E) in and Fig function the.1a ,1 bindingb , ofthefunction magnetic computed magneticof field magnetic ground strength field fieldfield strength strengthstrength for = ,3 forforfor.044 confinement = and3.044 for variousfrequency andand for values various of d. values of. d.The βsolidβ plot of the Fig.2 displays the energy of the donorstrengthππππ impurity, is greatly functionenergy reducedππππ of asΟc anda function asfor threethe distancestemperatures of the magnetic(d) (5K, increases 100K, and 200K) as :shown by Figs. 2, 3 and 4. * * c c 0 0 basis increases. ** β β Ο Ο Ο Ο β π π π π π π π π energy (BE) against the magnetic a) fieldΟ= strength3.044 R and b) Οfor =various 5.412 R . values of d.For For c c = =3.04430.044 and andand d=0 d=0d=0 a ,a the, the 0binding binding energy energy increases increases as asthe the magnetic magnetic field field Ω§ c * 0 *00 For =*3* .044 systemand Οd=0 indicates a ,Ο theΟΟ thebinding absenceΟπ π π π energy of the increases π π π π impurity, as and Οthe the magnetic dashed onefield indicates the presence fieldstate energiesstrength (E) , offor the confinement donor impurity frequencyFig. Hamiltonian 10. The ground=-state 5against.For412 binding R the .energy =The 3number.044 forsolid d = 0.1 of plot anda basis at constantofd=0 the(n) a pressur, thee (P=10binding kba and energy increasesβ β as the magnetic field energy of the donor Hamiltonian enhances as the, for confinement specific valuesstrengthIn addition, of( )theand increases figures versus demonstrate values of that athe, thebinding binding energy energy increases increases as0 0magnetic as the field magnetic = * β = * β Ο Ο π π π π π π π π Οc 2 R , and temperatureβ for (0 Ο0 3.044 R dashed line strengthstrength increases. increases. This This behavior behavior persists persists for for all all d- values.d-values. However, However, the the binding binding energy energy (d).Figc .Fig.2 display 4a ,4b,4c,4ds the energy show of thethe dependencesdonor0 impurity0 of energy the as afield function strength of the magneticincreases. This behavior persists * * 0 and ΟΟ= 5.412 RstrengthΟ* for the solid line).π π π π increases.π π π π Thisof the behavior impurity. persists It is forclear all from d-values. Fig. 2However, that the effectthe binding of the energyimpurity is to decrease the from 3.044 R to 5.412R . Thissystemfrom energy 1 toindicates behavior38 forΟ frequencythe agrees absence with of our= the 5 expectation. . 412impurity, and theΟ, impurity and parabolic Ο the dasheddistance strengthconfinement one d0 =increases. indicates0 strength and Thisthe0.5s presence behavior , iandncrease. persists for all d-values. However, the binding energy ground state binding energy (BE) on the magnetic * for all d-values. However, the binding energy Fig. 11β . The variation of binding energy forβ d=0.1a againstβ the Οc at fixed temperaturedecreasesdecreases (20K) as asthe the impurity impurity (d) (d) increases. increases. We We can can see see a significanta significant decrease decrease in inthe the binding binding field strengtho , for confinement frequency = 5.412R . The solid plot of the field strength for c different values of impurity decreases decreases as =the0 impurity** energy as the (d) of impurityincreases.= the system. (d)We increases.can The see presence a significant We canof donor decrease impurity in the bindinglowers the energy of the at magnetic field strength Ο = 2 . Theforπ π π π threefigures pressure clearly valuesdecreases show (0, 10, theand as20numericalππππ kbar)the impuritya) for Οstability00ππππ 5.412 (d) Rb increases.in ) and for Ο We 3.044 R can see . a significant decrease in the binding of the impurity. It is clear from Fig.Ο *2 that the effect of the impurity is to decreasππππ e the * * β * * * * * Furthermore, we have investigated the impuritydistances ground : -(a)state d=0c eigenenergy β a ,Fig. (b) 12In d=0.1. The Table (E) variationa and 3, ,and of wethe ground (c) have -d=0.5state listed0 bindinga the energy donorsee for d=0.1 aimpurity significanta as a function energy ofdecrease theandenergy pressureenergy binding in as the asd energyincreases d bindingincreases as afroenergy from md=0.1 d=0.1as a ato tod=0.5 d=0.5 a .a For. For example, example, at at = =3.0443.044 and and system indicatesc Ο the absence of the impurity, andΟ the dashed= * one= indicates** the=* presence ** * ** at fixed temperature (20K) and Οenergyc * 2 R foras Οd00 increases 3.044 R and Οheterostructure from 5.412 R d=0.1. a energyto d=0.5 due ato. itFor negative example, =coulomb3 .at044 attraction.= 3.044 and ourenergy computed of the and scheme.system. two The TheconfinementΟ ground presenceπ π π π state of frequenciesapproaches donor impurity a limiting(Οenergy0 = lowers3.044 asvalue d Rtheincreases as enerthed numbergyincreases fro ofm d=0.1the of from a to d=0.1 d=0.5 a ato. d=0.5For example, a . For atexample, and β β Fig. 13. The binding energy for d=0.5a* at constant pressure (P=10 kbar) as a function of Ο for 0 0 binding energy (BE) against the magnetic field strength , *forfunction specific of values magnetic of field strength for = 3.044 and for various=c =2 2 thevalues the binding bindingof d. energy energy reduces reducesβ significantly significantlyβ from from 4.62499 4.62499 ΟR Ο*R to* to2.55177 2.55177π π π π π π π π R *R. *. and Ο = 5.412R ). The binding energy (BE), against at **and the binding energy 0 of the 0impurity. It is clear fromthree temperatures Fig. 2 that (5K, the 100K, effect and 200K) of .the a) Οimpurity= 3.044 R is and b) Ο to decreas= 5.412 Re the . 0* Ο * * π π π π * basisheterostructure increases. energy due to it negative coulomb attraction. = 2 the =binding2 00 the energy binding reduces energyβ significantly reduces significantlyβ from β 4.62499* from ΟR 4.62499 to 2.55177 Rπ π π π to R 2.55177. R . the magneticc field strength, is greatly0 reduced* as c reduces0 significantlyThe energy= from*ofc cthe 4.62499heterostructure R to 2.55177 shows a significant dependence on the impurity Fig. 14. The binding energy for d=0.5 a *at constant pressureβ (P=10 kbar) and Οc 2 R against and versus values of (d). Fig.4a ,4b,4c,4d show the dependenceΟ Fors of th=e ground3.044 stateΟ and d=0 aβ , theΟ binding* Ο energy increasesπ π π π This ΟasThisΟ theresult result π π π π magnetic π π π π is isdue due tofield tothe the great great reduction reduction in inthe the coulomb coulomb imp impurityurity energy energy (Eq. (Eq. 4), 4), as aswe we theenergy distances of the (d)system. increases Thetemperature presenceas shown for( Οof =by 3.044 Rcdonor Figs.* for the impurity2, 3c dashed R lowers line and for . This the resultΟ ener= 5.412 isgy dueR * solid line).of tothe the great reduction in the β 0ThisΟ resultπ π π π ThisisΟ due result toπ π π π the is greatdue to reduction 0the great in reduction the coulomb in the imp coulomburity energy impurity (Eq. energy 4), as (Eq.we 4), as we 0 position. Increasing the impurity distance (d), changing the system from 2D to 3D binding energy (BE) on the magneticFigThe. 2energy display field ofsstrength andt hethe energy 4.heterostructure In, addition,forof the different donorstrength shows the Οvaluesimpurity increases.a figures significantof impurityenergyπ π π π This as dependencedemonstrate behavior a function persists thatonof thecoulomb for magneticimpurity all d- values.impurity However, energymentioned the(Eq. binding 4), earlier. as weenergy The mentioned same qualitative behavior can also be observed in Table 4 with heterostructure energy due to it negative coulomb attraction. mentioned earlier. The same qualitative behavior can also be observed in Table 4 with the binding energy increases as magneticmentioned mentionedearlier.field Theearlier. earlier. same The qualitativeThe same same qualitativequalitativebehavior can behavior behavioralso be can observed can also also be in observed beTable 4 inwith Table 4 with fieldposition. strength Increasing , for theΟ confinementc impurity distance frequency (d) , changing= 5.412 theR system. The solidfrom plot2D ofto the3D(bulk), as displayed clearly in Fig.3. For fixed values of impurity position (d), the distances : (a) d=0 , (b) d=0.1 , and (c) d=0.5 and theand two parabolic confinementdecreases confinement as frequencies the impurity strengths (d) increases. Ο0 Weobserved can see a in significant Table 4 different decrease withdifferent different quantitativein quantitative the binding behaviorquantitative behavior for for = =5.4125.412 . . β β β β different quantitative behavior = 5 .for412 = 5.412 . increase.Thec energy of the heterostructure0 showsdifferent a significant quantitative dependencebehavior behavior foronfor the impurity . β β * * Ο Ο * * 0 0 ( =3.044 R and ππππ =5.412Rsystem(bulk),)ππππ. The indicatesas bindingdisplayed the energy absenceclearlyππππ (BE inof), theFagainstigenergy .impurity,3. theFor as magnetic fixed dand increases thevalues fielddashed fro of m impurityone d=0.1 indicates apositionto thed=0.5 To presence(d), seea .the For the example, effects atof pressureβ = 3.044 and β temperature and Ο Ο π π π π π π π π In Table 3, we have listed the donor impurity 0 Ο0 π π π π position. Increasing the impurity distance (d), changing the system fromΟ 2D to To3DTo see π π π π see the the effect effects βofs ofpressure pressure and and temperature temperature parameters parameters on on the the binding binding energy energy of ofthe the 0 0 energy and binding energy as a functionTo ofsee theparameters effects of pressure on the and binding temperature0 energy parameters of the donor on the binding energy of the strengthππππ , is greatly reducedππππ asof the the distances impurity. (d) It increasesis clear from as shown Fig. 2 by =that 2F ig thes. the 2,effect 3binding and of To 4the. energysee impurity the reduceseffect is tos of decreassignificantly pressuree the and from temperature 4.62499 ΟparametersR* to 2.55177 onπ π π π the R* .binding energy of the material material Ω© bulk), as displayed clearly inβ Fig.3. For fixed values of impurity position (d), donorthedonor impurity, impurity, we we have have inserted inserted the the pressure pressure and and temperature temperature dependent dependent) c donor impurity, we have inserted the pressure and temperature dependent material In addition, the figures demonstrateenergy thatof the bindingsystem. energyThe presence increasesThisΟ result ofas π π π π donormagnetic is due impurity tofield thedonor greatlowers impurity, reduction the enerwe in gy havethe of coulomb insertedthe imptheurity pressure energy and (Eq. temperature 4), as we dependent material 383 Ω© Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019 and the parabolic confinementheterostructure strengths energy increase. due to it negative coulomb attraction. Ω‘Ω Ω‘Ω mentioned earlier. The same qualitative behavior can also be observed in Table 4 with Ω‘Ω Ω‘Ω c 0 Ο ππππ different quantitative behavior for = 5.412 . The energy of the heterostructure shows a significant dependence on the impurity Ω© β In Table 3, we have listed the donor impurity energy and binding energy as a Ο0 π π π π function of magnetic field strengthposition. Increasingfor = 3the.044 impurity and forTodistance varioussee the (d) effectvalues, changings of d.pressure the system and temperature from 2D toparameters 3D on the binding energy of the β c 0 For = 3.044 and d=0 (bulk),a*, theΟ a sbinding displayedΟ energy clearly increasesπ π π π in Fig donor.as3. theFor impurity, magnetic fixed values we field have of impurityinserted positionthe pressure (d), theand temperature dependent material β 0 strengthΟ increases.π π π π This behavior persists for all d-values. However, the binding energy
Ω‘Ω decreases as the impurity (d) increases. We can see a significant decrease in the binding
Ω© * * energy as d increases from d=0.1 a to d=0.5 a . For example, at = 3.044 and β 0 = 2 the binding energy reduces significantly from 4.62499 ΟR* to 2.55177π π π π R*. β c ThisΟ resultπ π π π is due to the great reduction in the coulomb impurity energy (Eq. 4), as we mentioned earlier. The same qualitative behavior can also be observed in Table 4 with different quantitative behavior for = 5.412 . β Ο0 π π π π To see the effects of pressure and temperature parameters on the binding energy of the donor impurity, we have inserted the pressure and temperature dependent material
Ω‘Ω energy of the donor Hamiltonian enhances as the confinement strength ( ) increases parameters of GaAs , ( (parameters, ) of (GaAs, ) ), ( , in (the, present ) calculations( , ) ) ,. inIn theFig present. 5 calculations. In Fig. 5 * * Ο0 from 3.044 Renergy to 5.412R of the . donorThis energy Hamiltonian behavior enhances agrees withas the our confinement expectation. strength ( )energy increases of the donor Hamiltonianβ enhances as theβ confinement strength ( ) increases to Fig.16 , we have shownππππ explicitlyππππto ππππFig.ππππ16ππππππππ the, weβ behavior haveππππ ππππ shown ofππππ the explicitlyππππ donorππππ ππππ ππππππππbinding theβ behaviorππππ energyππππ of (B theE) donoras a binding energy (BE) as a energy0 of the donor Hamiltonian enhances as the confinement strength ( ) increases0 from 3.044 R* to 5.412R*. This energy behavior agrees with our expectation.Ο from 3.044 R* to 5.412R*. This energy behavior agrees with our expectation.Ο Furthermore, we have investigated the impurity ground -state eigenenergy (E) and the function of the magnetic field strength 0 , taking in consideration the impurity from function3.044 R * ofto 5.412Rthe magnetic*. This energyfield strength behavior agrees , taking with in our consideration expectation.Ο the impurity c Οc binding energyFurthermore, (BE) against we havethe magnetic investigated field the strength impurity ,ground for specific -state valueseigenenergy of position (E)Furthermore, and (d), the temperature we have (T), positioninvestigated pressure (d), (P) temperaturethe andΟ impurity confinement (T), ground pressure frequency -state (P) eigenenergyand confinement. Fig. 5 a,(E) 5b and frequency the . Fig. 5a, 5b c Furthermore,0 we have investigated the impurity ground -state eigenenergy (E) and the Ο Ο 0 0 and versus bindingvalues of energy (d). Fig (B.E4)a against,4b,4c,4d the show magnetic the dependence field strengths of th ,e forground specific stateshow values binding the of donor energy binding (BE )energ againstshowies the againstthe donor magnetic the binding magnetic field energ strengthfieldies strengthagainst , fortheforΟ specificmagneticthree different values field strength of forΟ three different
c binding energy (B0E) against the magnetic field strength , for specificc values of 0 binding energyand (versusBE) on values the magnetic of (d). fieldFig. 4strengtha ,4b,4c,4d , forshow different the dependence Οvalues ofs impurityof thetemperatures ground and versus stateΟ (5K, values 100K, of and(d)temperatures. 200K)Fig.4a and,4b,4c,4d (5K, fixed 100K, valuesshow and theof 200K) pressure,dependenceΟ and impurityfixeds of valuesth positione ground of pressure, stateΟ impurity position c 0 c and versus values of (d). Fig.4a ,4b,4c,4d show the dependenceΟ s of the ground stateΟ distances : binding(a) d=0 energy, (b) (d=0.1BE) on ,the and magnetic (c) d=0.5 fieldΟ and strength two confinement , for different frequencies valuesd=0 of binding impurity and confinementenergy (BE) frequencyond=0 the magnetic and confinement= 3 field.044 strengthR . frequencyFor fixed, for temperature, different= 3.044 valuesR the. Forfigure of fixed impurity temperature, the figure β β β β β β energy of the donorβ Hamiltonian0 enhances as the confinement strength ( ) increases * * c binding energy (BE) on the magneticππππ field0 strength , for differentc Ο values of impurity ( =3.044 distanceR and sππππ : =(a)5.412R d=0 )ππππ., The(b) d=0.1binding ,energy andππππ (c) (BE d=0.5), againstΟ and thetwo magnetic confinement fieldclearly frequenciesdistanceππππ showss the: (a) enhancement d=0 clearly, (b) d=0.1of shows theΟ binding, theand enhancement (c) energy d=0.5 asΟ theandof the magnetictwo binding confinement field energy strength frequenciesas the magnetic field strength * * 0 β β β β from 3.044β R to c5.412Rβ. This energy behavior agrees with our expectation.Ο 0 0 energy of thedistance donor Hamiltonians : (a) d=0 enhances, (b) d=0.1 as the, andconfinement (c) d=0.5 strengthΟ and two ( confinement) increases frequencies strengthππππ , is greatly reducedππππ * as theππππ distances *(d)ππππ increases as shownππππ by Figs. 2, 3 and 4. increases.= This *enhancementππππ = increases. in the*ππππ donor This enhancementbinding energyππππ in canthe donorbe attributed binding to energy the can be attributed to the ( =3.044 R and =5.412R ). The binding energy (BE), against the magnetic( field3.044 Rβ and 5.412Rβ ). The bindingβ energy (BE), against the magnetic field * * * *c 0 0 0 from 3.044 R( to =5.412R3.044c 0 R. This and energy ππππ =5.412R behavior0Ο )ππππ. Theagrees binding with our energy ππππexpectation. (BE),Ο against the magnetic field In addition, strengththeππππ figures, is greatlydemonstrate reducedππππ that as the the binding distances energy (d) increasesincreases asas shown magnetic by FfieldigparabolicΟs. 2,strengthππππ 3 and magnetic , 4is. greatly confinement reducedππππ parabolic asFurthermore,term the magnetic distances inconfinementwe E(d) q.have (increases3). investigated For term fixed as shown values the inimpurityby of E Fq.magneticig (s3).. 2,ground For 3 and fixed -4state. values eigenenergy of magnetic (E) and the energy of the donor Hamiltonian enhances as the confinement1 2 strength2 ( ) increases ππππ0 ππππ0 1 2 2 energy of the donor Hamiltonian enhances as the confinement strength ( ) increasesstrength , is greatly reduced as the distancesbinding4 (d)energy increases (BE) asagainst shown the by4 Οmagnetic FigΟ s. 2, 3field and strength4. , for specific values of and the Inparabolic addition, confinement the figures strength demonstrates thatincrease. the binding energyFurthermore, increases we as magnetichaveIn investigated addition, field the the figures impurityfield demonstrate groundstrength Ο -thatstateΟ , the theeigenenergy bindingbinding energyenergy (E) and increasesdecreases the as when magnetic0 the temperature field increases, as field strengthfrom 3.044 ,R *the to 5.412Rbinding* .energy This energy decreases behavior when agrees the temperature with our expectation. increasesΟ, as energy of the donorenergy Hamiltonian of0 the donor enhances Hamiltonian as the confinementenhances as strengththe confinement ( ) increases strength ( ) increases c * * 0 Ο In addition, the figures demonstrate that the bindingc energy increases as magnetic field c 0 fromΟ 3.044 R to 5.412R . Thisenergy energy of behavior the donorππππ agrees Hamiltonian with our expectation.enhances as the confinement strengthc ( ) increasesclearlyand shown versus Οin Fvaluesig.5a. Similarof (d). Figbehavior.4a ,4b,4c,4d of the donor show binding the dependence energyΟ is sdisplayed of the ground in stateΟ and the parabolic confinement strengths increase.binding energy (BclearlyE) against shownand thethe Οin parabolicmagnetic Fig.5 a. Similar confinementfield strength behavior strength 0 of , thefors donorspecific increase. binding 0values energy of is displayed in In Table 3, we have listed the donor impurityfrom energy3.044 R and* to from5.412Rbinding 3.044* .energy This R* energyto as 5.412R a behavior*. This agreesenergy with behavior our expectation. agrees withΟ our expectation.Ο Furthermore, we have investigated the impurity ground -state eigenenergy (E) and the c * * 0 and thec parabolic confinement0 Fig .strength5bbinding for different,s energyc increase. (B=E0)5 on. 412 the magnetic. 0field strength , for different values of impurity Furthermore,Ο we have investigatedfrom 3.044the impurity R to 5.412R ground. ππππThis-state energy eigenenergyand behavior versus (E) agrees valuesand the Fwith igof . 5Ο (d)bour for. Figexpectation. different,.4a ,4b,4c,4dΟ = 5 show.412 the. dependenceΟ ππππs of the ground stateΟ function of magneticIn fieldTable strength 3, we have for listed the= 3 donor.044 impurity and for energyvarious and values binding cof d. energy asIn aTable 3, we have listed the0 donor impurity energyβ and binding energy as a energy of the donor Hamiltonian enhances as the confinement strength ( ) increasesΟ binding energy (BE) againstβ the magneticππππ 0 field strength , for specific valuesc of Furthermore,β we Furthermore,have investigated we have the impurityinvestigated ground the 0impurity-state eigenenergy grounddistance -states (E) : (a) andeigenenergyΟ d=0 the , (b) π π π π (E) d=0.1 and the, and (c) d=0.5 Ο and two confinement frequencies c 0 binding energy (BE)In on Table the magnetic 3, we haveΟ field listed strength theπ π π π donor, for impurity different energy values and of impurity binding energy as a binding =energy3.044 (B E) against the* magneticΟ fieldΟ strengthπ π π π , for specific values of In Fig.6 we have shown the dependence of the donor binding energy on the For function* andof magnetic * d=0 Furthermore,a , fieldthe bindingstrength we energy have for investigated increases= 3.044 asthe the impurity and magnetic0 for groundvarious field - valuesstatefunctionIn eigenenergy ofFig d.of.6 magneticwe have (E) shownandfield the strength the dependence for of =theβ3 .044donor binding andc β for energy various on values the β of d. 0 from 3.044 R to 5.412R . This energy behavior agrees with our expectation.Ο and versus values of (d). Fig.4a ,4b,4c,4d* show the dependenceΟ* s of the ground stateΟ β binding energyc (BbindingEβ) against energy the (magneticBE0) against field the strength magnetic( field,) for strengthspecific( (c=3.044 values) , Rfor of andspecific ππππ = values5.412Rβ of)ππππ . The binding energyππππ (BE), against the magnetic field 0 Ο distances : (a)functionparameters d=0Ο of, (b)ofmagnetic GaAs d=0.1 , (field , and strength ,(c) d=0.5 Οfor and , two )c= , 3inconfinement.044 the0 present and frequenciesforcalculations various . values In Fig .of 5 d. and versusΟ valuesπ π π π of (d). Fig.4a ,4b,4c,4d *show cthe dependence0 s of the ground statetemperature for fixed valuestemperature of pressure* for (P=10fixed valuesKbar), of p=ressure2 ,(P=10 = 0Kbar), and = 2 , = 0 and strength increases.For This= 3 .behavior044 binding and persists d=0 energy fora , all the(B ΟdE -)bindingvalues. againstΟ However, energythe magnetic increases π π π π the binding field energyas strength theenergy ofmagnetic the For donor, for field specific=Hamiltonian 3.044 valuesβ c andenhances of d=0 aas, thetheΟ confinementbindingΟ energy0 strength increasesπ π π π ( ) as increases the magnetic field β binding energyβ (BΟE) on the magnetic0β Οc field strengthΟ β0 , for differentΟ 0 values of impurity β β β and versus valuesand of versus(d). Fig values.4*a ,4b,4c,4d of (d). Figshow.4a *the,4b,4c,4dππππ dependenceππππβ ππππ show*ππππππππππππs strength theππππofcβ thdependenceππππeππππ ,ground 0is greatly sstate of reducedππππ the ground as the state distancesβ (d)β increasesc as shown by Figs. 2, 3 and 4. Furthermore, we have investigated the impurity ground -state eigenenergy= (E) andto Fig. the16 ππππ= c, =3we.044 have shownππππ explicitly theΟ0 ππππ behaviorΟ of the donorπ π π π bindingc energy (BE) as a binding energy (BE0 ) on the magnetic field strength , for different( values3.044 of impurity RFor and 5.412R0 )and. The d=0( binding a=various, 3the. 044energy bindingconfinements (BEand ),energy against= ( 5 .increases412 the= 3R magnetic.044)Ο as the and π π π π field0 magnetic ππππ= 5.412 ππππfield R )Ο. The bindingπ π π π ππππ energyππππ again decreases asstrength the impurityΟ increases. (d) increases.π π π π andThis versus behavior We values can persists see of a(d) significantfor. Figall .d4-avalues. ,4b,4c,4ddecrease However, inshow the bindingthe bindingdependenceS.various Abuzaid Οstrength* energyconfinementsΟ ets al.increases.of *the groundπ π π π This behaviorstateΟ persists for all d-values.. cThe However, bindingΟ energythe binding again energy from 3.044 R to 5.412Rβ . This energy behavior agrees with our expectation.Ο β β binding energy (BbindingE)0 on the energy magnetic (BE)0 fieldon0 distancethe strength magnetics : (a) ,field for d=0 differentstrength, (b) d=0.1valuesβ, for of,different and impurity (c) d=0.5values β of and impurity two confinement frequencies c functionΟ of the π π π π magnetic field0 strengthIn addition, , taking the0 figures in0 consideration demonstrate thethat 0impurity the binding energy increases as magnetic field distancebinding senergy : (a) d=0(BE ) against, (b) d=0.1 the magnetic,* and (c) field d=0.5 *strengthΟ and two , forconfinement specificstrengthππππ values , frequenciesis greatlystrength of reducedππππ increases. as the This distances behaviorΟ shows(d)β persists increases a π π π π clear for asallβdecreasing Ο shownd-values.Ο by behavior However,Figs.β 2, π π π π 3as andthe the binding 4Οtemperature. energy of the system increases. The energy as ddecreases increases asfro them impurityd=0.1binding a (d)to energy d=0.5increases. ( BaE. ) ForWeon the example,can magnetic see a atsignificant field= strength3. 044decrease and ,shows infor thedecreases different bindinga clear as valuesdecreasing the impurity of impurity behavior (d) increases. as the temperatureWe can see ofa significant the system decrease increases. in theThe binding β β β ( =3.044Ο Rc * and ππππ =5.412RΟc *)cππππ. The binding energyππππ (BE), against the magnetic field impurity, we distance have inserteds c : (a) d=0 distance the , pressure(b)s Furthermore, :d=0.1 (a)position βd=0 and,0 and (d), , we (b)(c) temperature have d=0.1ofd=0.5 the investigated , system andand (T), two(c) pressure increases. d=0.5theconfinement impurity (P) andand andΟ The the two groundfrequenciesconfinement parabolicdependence confinement -state confinement frequencyeigenenergy frequencies of the strength (E). Fig and. 5sa, the 5b increase. * and =versus values* ofππππ (d)=. Fig.4a* ππππ,4b,4c,4d show theππππ dependenceΟ s Inof 0 addition,the ground thedecreases statefigurescΟ as demonstrate the impurity that (d) the increases.dependence binding We energy ofcan the seeincreases material a significant as parameter magnetic decreases* likefield in the the effective binding mass m (P,T) and dielectric ( 3.044 R and 5.412R ). The binding *energy (BE),* againstΟ the*β magneticπ π π π Ο fieldβdependence* β of theββ material parameterβ s like* the effective* mass* m (P,T) and dielectric = 2 theenergy binding as d energyincreasesdistance reduces temperaturefroms d=0.1significantly: (a) d=0a to dependent d=0.5, from(b) d=0.1 a4.62499. For material , example,and R (c)to 2.55177d=0.5 parametersat = andR3.. 044energytwo confinement0 material andas d increases parameters frequencies fro0 m d=0.1 like the a toeffective d=0.5 a . Formass mexample,(P,T) at = 3.044 and = * ππππ = * *ππππ ππππ strengthππππ , *isππππππππ greatly reducedππππ ππππasc the distances (d) increases as shown0 by Fig0 s. 2, 3 and 4. 0 β 0 * ( β 3.044 R βand( =3.0445.412Rbinding Rshow andβ) . energyThe the bindingdonor= 5.412R(BβE )binding energyagainst). The energ (BEthe binding ),iesmagnetic against against energy*Ο thefield the (BEmagnetic magneticstrength), *against field field the , forstrength magnetic specific for Οfield threevalues different of ππππ ) β * bindingππππc energy (BE)ππππ on the magneticof GaAsfield strength , ( m(PT ,, )for and differentβ ( PT ,) )values ,and in the theof impurityparabolic energy present as confinement denergy increasesand( of dielectric) the strengthfro donorm d=0.1 sconstant constant Hamiltonian a increase.to d=0.5( , enhances )a on.on For thethe asexample, temperature temperaturethe confinement at and = 3strengthpressure.044 ( andexplain * increases in Table 1, where m strength, is greatly reduced as the distances (d)* increases as shown* by Figs. 2, 3 and0* constant4. *, on the temperature andIn Table pressure 3, we explain have listedin Table the donor1, 0*where impurity m energy* and binding energy as a ThisΟparameters resultπ π π π is of due GaAs= to2 the , (the great (binding ,(reduction ) = energy3.044 in ( R thereduces, and coulomb) ) ππππ , insignificantly= the5.412R imp presenturity)ππππ. Theenergy from calculations binding 4.62499 (Eq. 4),energy. ΟInR ππππas Fig towe (BE . 2.55177 5 ), againstπ π π π = 2 R . thethe magneticbinding energyfield reduces significantly* from 4.62499 ΟR to 2.55177π π π π R . calculations. In 0Fig. 5 to Fig. 160 ,0 we have shown0 and pressure explain in Table 1, wherec m decreases β0 0 strengthππππ c , is greatlystrengthππππ reducedππππc , is asgreatly thetemperatures distances reducedππππ In addition, (5K,(d)as theincreases 100K, distances the* andfigures as shown200K)(d) 0 demonstrateincreases* byand Fππππ igfixed sas. 2, that shownvalues 3 andtheΟ by ofbinding4. Fpressure,igs. 2,energy 3 impurityand0 increases4. position asΟ magnetic field β β Ο Ο and versus valuesfrom ππππof 3.044 (d)β . RFig to.4 a5.412R ,4b,4c,4ddecreasesππππ . This ππππ showand energyππππ ππππ the increases behaviordependence with agrees sincreasing of with thΟe * ourground T expectation. which stateπ π π π diminish Ο* donor impurity binding Indistance addition,s : (a)thec d=0figures, demonstrate(b) d=0.10explicitly , thatand the(c) the bindingd=0.5 behavior0 energy and twoof increases the confinement donor as bindingmagnetic frequencies energy field=decreases2 c theππππ andbindingππππ ππππ increases increases energy withreduces with increasing increasing significantly T which T whichfrom diminish 4.62499 diminish donor R toimpurity 2.55177 binding =R 3. .044 mentionedto Fig.16 ,earlier. ThisweΟ have result Theπ π π π shown issameππππ due explicitlyππππ qualitativetostrengthππππππππ theππππ ππππππππgreat the, is βbehavior behaviorgreatlyreductionππππ ππππ reducedcanππππ of in thealso the donor ascoulombbe the observed binding distances imp inenergyurity (d)Table energyincreases ( B4E) with as(Eq. aasThis Ο 4), shown asresult weπ π π π by is F dueigs. to2, 3the and great 4function. reduction of magneticin the coulomb field strength impurity energy for (Eq. 4), as we and for various values of d. β β β In Table 3, we β have listed the donor impurity energy and binding energy as a (BE) as a functionIn addition, of the the magneticfiguresIn addition, demonstrate bindingfield thed=0 cfiguresstrength energy that and demonstratethe (confinementB andEbindingdonor) on the ππππthe impurityparabolic energythat magneticfrequency the increases binding confinementbinding field = strengthenergyas energy3 .magnetic044 strength ππππ increases R (BE). , Forfor fields . fixeddifferent as imagneticncrease. temperature, values field of theimpurity figure β ( =3.044 R* and ππππ =5.412Renergy*)ππππ. The of bindingthe donor energy Hamiltonianππππ (BE), against enhances the magneticas the confinementΟ field π π π π strengthππππ ( ) increasesenergy (BE) . ππππ c 0 and the parabolic confinement strengths increase. This energyresultβ is(B dueE) . to the great reduction in the= coulomb3.β044 impurity energy* Ο(Eq. 4),Ο as we π π π π different quantitativementioned behavior earlier. InforThe addition, same,= taking5 qualitative. 412the figuresin .consideration behavior demonstrate can alsothethat impuritybethe observed binding position energyin Tablementioned increasesFurthermore, 4c withIn earlier. asFig.7a magnetic we The,7b, have same thefield investigated= Forbehavior 3 qualitative.044 theof behavior theimpurity donor 0and can ground d=0bindingalso a be-state, observedthe eigenenergybinding in Tableenergy (E) 4 andwithincreases the as the magnetic field function of the magnetic field strength , taking in considerationfunction theof magneticimpurityππππ fieldΟ strength for Ο0 andc for variousππππ values of d. c0 0 * 0 β and* the parabolic and confinement thedistance parabolicclearly strengths : showsconfinement(a) d=0s the ienhancement,ncrease. (b) strength d=0.10 s ,of and theincrease. (c) binding d=0.5 energyΟ and twoasβ the confinement magnetic fieldfrequencies strength strengthΟππππ , is greatly reducedππππ as fromthe (d),distances 3.0440 temperature R (d) ππππto 5.412Rincreases (T),. Thispressure as shown energy (P)by behavior andFigs .confinement 2, agrees 3mentioned and with4. our earlier. expectation.energyIn The Table Οsame had 3 , qualitative beenwe have shown listed behavior0 β asthe adonorcan function also impurity be observed ofenergy the in and Table binding 4 with energy as a Ο cπ π π π bindingβ *energyc (BEI)βn 0against Figstrength.7a ,the7bΟ, themagneticincreases. behaviorβ π π π π field This of the strengthbehavior donor binding persists , for energyspecific for all had dvalues-values. been ofshown However, as a functionthe binding of energy positionIn (d),Tabledifferent temperature 3, we quantitative have (T), listed pressure behavior frequencyand the thedonor (P) parabolicfor andΟ impurity confinement =. Fig. confinement5c.412 energy5a, 5b . frequency andshow strength bindingFor the s donor energy =. Fig3 increase..044 .binding 5asa, I n5ba F and different ig .7 ad=0 ,7bmagnetic0 ,quantitative athe, thebehaviorΟ binding fieldbehavior ofΟ the energy strength donor for increasesbindingπ π π π = for5. 412energy differentas the .had magnetic been values shown field as a function of To see the effects of pressure and temperature parametersΟ on the bindingΟc energy of increases.the * Thisππππ enhancement* ππππ in0 the donor binding energy can be attributed to the β ( =3.044 R and ππππ =5.412R )ππππ. The binding energyππππ (BE),β against the magnetic field In addition, the figures demonstratec energies that the againstbinding energy the magnetic increases as fieldmagnetic0 strengthdifferent fieldβ quantitative for functionof parameters:of behavior magnetic for field =strength5.412 . for+ = 3.044 ,and c for various values of d.0 0 In Table 3 , we have0In0 Table listed 3 ,the we donor have impuritylisted the energydonorthe impurityand magnetic decreasesbinding energy0 energy fieldas theand strengthimpurity asbinding a (d)energy , increases. Οfor as adifferent We can values see a significantof parametersΟ decrease : in the= binding show the donor binding energFurthermore,Οies against the weΟ magnetic =have3.044 investigated fieldπ π π π strength thestrength impurityforΟΟ threeππππ increases. ground differentc π π π π the This- state magnetic andbehavior eigenenergy versus field persists values (E)strength for andof all(d) the d. - Figvalues. , .4forΟa ,4b,4c,4d However,different π π π π show thevalues binding the ofdependence energyparameters s of : the ground= state donorfunction impurity, of magnetic we havefield strengthinserted three theIn for differentTablepressure 3, weand temperatures havetemperature listedand for the (5K,variousdependent donor 100K, valuesimpurity 0materialandΟ of 200K) energyd. andpressure binding0 energyP=0, 10, as anda 20 kbar,β impurity positionβ To see the effects of pressure and temperature parameters on thestrength ππππbindingparabolic, isenergy greatlyTo magnetic see of reducedtheππππ effectconfinement ass ofthe pressure distances term0 and (d)* temperature increases in Ecq. (3). as parameters0 Forshown fixed by values Fonig thes. 2,of binding 3magnetic and 4energy. of the 5.412β and = 3.044 R , pressure P=0,= 10,3*.044 and 20 kΟbar,c impurityπ π π π Ο positionΟ c π π π π 0 0 and the parabolic confinement strengths increase.function of magneticfunction field of strength magnetic field forFor strength = 3a.044 for and and for= d=0 3various1.044 2a ,2 thevalues and binding for of various d. energy Οvalues increases of d.* as the magnetic* field Ο * andc fixed0 values of pressure, impurity position bindingd=0 energy, and (BE ) temperature on Οtheenergy magnetic as d T=20 fieldincreases K.strength The fro m donor d=0.1, for differenta to d=0.5 values Οa . Forof impurity example, at = 3.044 and Fortemperatures = 3.044 (5K, 100K,and d=0 and bindinga 200K), theΟ bindingenergy and* Οfixed (BenergyE )values against increasesπ π π π of the pressure,β magnetic as decreasesthe impurity magnetic field as strength Tothepositionβ field seeimpurity the ,effect for(d) specificincreases.s of pressure values We βand can of temperaturesee a significant parameters decrease on in the the binding binding energy of the function of magnetic field strength for0 = 3.044 and for various valuesβ of d. 4 Ο Ο β c donor impurity, we haved=0 ainserted and 0confinement the pressure π π π π andfrequency temperatureΟ In addition,dependentfield strengthc donorthe material figures binding0impurity,0 , thedemonstrate binding energycwe have energy 0that shows inserted the decreases binding a significantthe pressureenergywhen the increases and increasetemperature temperature as magnetic as increases dependent field, as material β * Ω‘Ω‘ *Ο β ππππ d=0= ,3 and.044 temperature T=20* K. TheΟ cdonorstrengthΟ Οbinding *increases. Οenergyπ π π π π π π π This showsΟ behavior 0a significantπ π π π persists increase for all d-values.c However, the binding energy 0 . from 4.62499 ΟR to 2.55177π π π π R Ω‘Ω‘ For For and =d=03. 044a , the andβbinding d=0 energya , the* increasesbinding energyas* the= increasesmagnetic2 the asbindingfield the magnetic energyΟ reducesfield significantly 0 d=0Ο In and Table confinement 3π π π π , we have frequency listedand . versustheFor donorfixed =values3 .044impurity temperature, of R (d). Forenergy. Fig fixedβ.4 aandthe ,4b,4c,4dtemperature, bindingenergyfigurec show as energy0clearly dthe donorincreasesthe figureas dependenceshows aimpurity, Ο frodistancemthe d=0.1 s weof s magnetic thhave :a e(a) toground d=0 insertedd=0.5 state field, aΟ (b)the . Ford=0.1 pressureincreases; example,, and and at(c)as temperature d=0.5we= increase3.044 and dependent two and confinement material frequencies π π π π cβΩ‘Ω strength increases. This behavior persists = 3for.044 all d-values. However,* Ο theβ bindingΟ energy For and d=00 ππππ a , the binding energy andclearly theincreases shownparabolic Οinas Fconfinementtheig.5 a.magnetic Similar strength βbehaviorfield s of theincrease.ββ donorΟ , binding energyβ is displayed in β the enhancementβ as ofthe magnetic the binding field0 energy increases as; as decreases we theincreas magneticase the magneticimpurity field field(d)c increases. strengthstrength Wec , the can the see electron- a significantβ decrease in the binding 0 βstrengthΟ increases.strengthπ π π π ThisΟ behavior increases. persistsπ π π π This behaviorfor all d -persistsvalues.* However,for all d-Οvalues. the binding* π π π π However, energy the0 binding energy functionππππ of magnetic field strengthbinding Ο energy for (B=E3) .on044 the magnetic and for variousfield= strength2 values of , d.for different( =3.044 values R ofand impurity ππππ =This5.412R result)ππππ. The is due binding toΟ the* energy greatππππ (BEreductionπ π π π ), against* in the the coulomb magnetic imp fieldurity energy (Eq. 4), as we Ω‘Ω . reduces separation significantly distance from0 decrease 4.62499ππππ Rwhich to 2.55177in turn R Ω‘Ω decreasesclearly shows as the theimpurity enhancement (d) increases. theof 0the magneticWe binding can see energy a significantfield as strengththe decreasemagnetic increases. in field thec cthe bindingstrength binding This energyatom strengthΟ increases.π π π π This behaviorelectron-atom persists separation for ΟallΟ ddistance-Fvalues.ig.5b for However,decrease different, whichthe binding= in5. 412turn energy i.ncrease ππππs the electronππππ β β 0 0 * * = 3.044 enhancementc 0 decreasesin the donor as the binding impuritydecreasesc energy (d) as increases.the can impurityc be Weenergy (d) canincreases increases. seeas da significantincreases theWe can electron fro decreaseseem ad=0.1 significant confinement. in atheto binding d=0.5decrease a The .in For the bindingexample, binding at and Ω‘Ω s .can 2, 3also and be 4 . observed in Table 4 with Ο* Ο * π π π π ΟIn Tablestrengthππππ 3, we , haveis greatly listed reduced ππππtheβ donormentioned as theimpurity distances earlier. energy The(d) increasesand same binding qualitative as shownenergy behavior byas Faig * Forenergy increases. as= d3 .increases044 This enhancementand fro d=0m d=0.1 distancea , theina thetosbinding d=0.5 :donor (a) d=0 aenergy binding. For, (b)increasesexample, energy d=0.1 canatas, This andΟ thebe = (c)attributedresultmagnetic3 d=0.5.π π π π 044 is due tofield andand tothe thetwo great confinement reduction0 frequencies in the coulomb impurity energy (Eq. 4), as we β decreasesattributed as the toimpurity the confinement.parabolic (d) increases. magnetic The We binding can confinementsee energy a significant again shows decreaseenergy Οa great againin the enhancement bindingshowsπ π π π a great as the enhancement pressure as the 0 β β β ββ * In Fig.6= we2* have the* shownbinding the energy* dependence reduces of significantlythe donor binding from 4.62499energy on ΟR *the to 2.55177π π π π R*. c 0 * energy as d increases* energy0 fro asmfunction dd=0.1 increases aof tomagnetic frod=0.5m pressured=0.1 a field. For a strength toexample, increases, d=0.5 a at for. For while =example,= 3 keeping.0443.044 at and the and = magneticfor3.044 various and values= 5. 412of d. strengthΟ Ο increases.π π π π This behavior( persists=3.044 for R alland d -ππππvalues.=5.412R However,)ππππ. The Οthe binding* binding energy energyπ π π π ππππ (BE* ),In against addition, the magneticthe figures field demonstratedifferent quantitative that the binding behavior energy for increases as magnetic. field parabolic= 2 magneticthe binding confinement energy reduces termterm significantly in Eq.Eq. from (3).(3). For For4.62499 fixedfixed*mentioned Rvaluesvalues to 2.55177 ofof earlier.* magneticmagnetic R The. same qualitativeβ behavior can also be observedβ in Table 4 with energy as d increases froincreases,m d=0.1 while a to keepingd=0.5 athe. Formagnetic example, fieldc strengthat = unchanged.3.044 and β β β 1 field strength unchanged.c 0* 0 *0 β 0 2 2 0 = 2 temperatureThisΟ for result fixedπ π π π is valuesdue *to oftheΟ p greatressureΟΟ reduction (P=10 π π π π Kbar),inπ π π π theΟ *coulomb = 2 impπ π π π , urity 0*= 0energy and (Eq. 4), as we c ππππ field strength ππππ , the bindingthe binding energy= 2energy For decreasesthe reducesbinding= 3.044 significantlyenergy and and reducesthe d=0 parabolicfrom asignificantly , 4.62499the βconfinement binding R from to energy 2.55177 strength4.62499 increases sR R. to i ncrease. as2.55177 the magnetic ΟR . fieldπ π π π ThisdecreasesΟ resultπ π π π as is the due impurity to the great (d) increases. strengthreduction, Weis 4in Οgreatly thecanΟ coulomb see reduced a significant imp as uritythe decreasedistances energydifferent (Eq.in (d) thequantitative increases4), binding as we as behavior shown Inbyfor 0 F Fig.igs=. 2, 8,5 . 3412 weand take4.. the temperature T=20K,β β field strength , the binding energywhen= 2 decreasesthe binding temperature when energy theβ reducestemperature increases, significantly increasesβ as clearly from, as 4.62499β ΟR* to 2.55177π π π π R*To. see the effects of pressurec and temperature parameters on the binding energy of the Οc In Fπ π π π ig.8, we takec the temperaturevarious0 T=20 confinementsmentionedK,c = 2 (earlier. = 3 The.044= same0 β and parameters,parameters,qualitative = 5 .412whilebehavior while R 0)Ο. Thechangingcan bindingalsoπ π π π be ππππ energyobservedππππ again in Table 4 with * β * This result is dueThis Οto the result greatπ π π π strength is reductiondueΟ toincreases. the in greatΟ theπ π π π This coulombreduction behavior0 imp in persiststheurity coulomb energy for all (Eq.imp d-values.urity 4), as energy weHowever,ππππ (Eq. 4),the asbinding we energy mentionedenergy as dearlier. increasesc The fro samem d=0.1 qualitativeIn caddition,shown a to d=0.5behavior inthe Fig. figuresa . can 5a.For demonstrate also Similarexample, be observed behavior at that the=in 3 ofTablebinding.044 the 4 donorwithenergy and increasesthe pressure. asΟ magneticβ We fieldπ π π π observeββ a great enhancementβ clearly shown Οin Fig.5a. SimilarThisΟ behaviorresultπ π π π is dueof the to thedonor great binding reduction energy in theis displayed coulomb impin urity energyc In Table (Eq.0 34),, we as havewedonor listed impurity,0 the donor we impurityhave inserted energy the and pressure binding andenergy temperature as a dependent material binding energy is displayedchanging the in pressure.Fig.To see 5b thefor We effectdifferent, observeshowsβ s of a pressure greatclear enhancementΟdecreasing and π π π π temperatureΟππππ ππππππππbehavior in ππππthe donor parameters π π π π ππππas thebinding Οtemperature on energy the binding as of the energy system of increases. the The mentioned earlier.mentioned The0 same earlier. qualitative The samebehaviordifferentin qualitative the quantitativecan donoralso behavior be behaviorobserved binding can alsoforin energy Table be =observed 54 as .412with the in . pressureTable 4 with = 2 and the parabolic confinement strengthΟ * s decreases increase.π π π π *as the impurity (d) increases. We can see a significant decrease in the binding different quantitativethe binding behavior energy for reduces = 5significantly.412 . from 4.62499 R to 2.55177 R . =β 3.044 Fig.5b for different, = 5.412mentioned . earlier. The samethe pressure qualitative increasesdonor behavior impurity, for canconfinement alsowe havebefunction observedstrength: insertedincreases of in magneticthe Table =for 3pressure .044confinement 4 field with andstrength temperature =strength: 05.412 for R dependent. * material and for various values of d. β β dependence of the material parameters like theΟ effective π π π π mass m (P,T) and dielectric c c In Fig. 6 wedifferent have shownquantitative the behavior dependence0 for of= 5.412 . = 5.412* * β Ο β0 differentππππ quantitativeenergy as d behavior increasesand for from d=0.1 a toβ . d=0.5 This a behavior. For example, β is expected; at = 3.044 and Ω‘Ω ThisΟ resultπ π π π is due to the0 great reductionΟ in the π π π π coulomb impurity energy (Eq. 4), as we To see the effect0 s of pressure and*0 temperaturec 0 parameters on the binding energy of the Ο differenttheπ π π π donor quantitative binding behavior energy for on the= 5 temperature.412 . for For β = Ο3.044 andπ π π π β d=0 Οa , theΟ bindingΟ* energy increasesπ π π π as βthe *magnetic field To see the effects of pressure and temperatureIn Table 3parameters, we haveThis on listedbehavior the thebinding isdonor expected; energy impurity constant sinceof the energy0 as we( andincreas,since) binding one asthethe0 we energypressure,temperature increase as the a effectiveand the pressure pressure, mass explainm the effectivein Table 1, where m In Fig.6 we have shown the dependence of the donor binding energy onΟ the π π π π 0* * fixed values of pressure (P=10 Kbar), β = 2 the, binding energyΟ * reducesβ π π π π significantly from 4.62499 ΟR to 2.55177π π π π R . mentioned earlier. The same qualitative behavior Tocan see also the be effect observed0sTo of see pressurein theTable effect and4 withs temperature of pressuredonormass parametersandimpurity,0 temperaturem increases weon thehave parameters binding whileinserted energythe on the thedielectric pressureof binding the andconstantenergy temperature of the dependent material the binding energy Ω‘Ω ,function of *magnetic fieldincreases strength whileΟ forthe dielectricπ π π π = 3.044 constant β ππππandππππstrength ππππ for ππππ Οdecreases. various increases. valuesTheseπ π π π This ofchanges behaviord. in thepersists material for all d-values. However donor impurity, we have inserted da the= 0 pressure and various and temperature confinements dependent cmaterialdecreases and increases decreases. with increasing These changes T which indiminish the materialdonor impurity binding temperature for fixed valuesTo of see p ressurethe effect (P=10s of pressure Kbar), and =temperature2 , This Ο=parameters0 result π π π π and is on due the to binding the great energy reduction of the in the coulomb impurity energy (Eq. 4), as we different quantitative behavior for = 5.412 . The binding energy again showsβ ππππ donor impurity,* donorwec βhave impurity,0 inserted βwe the have pressure ππππinsertedparametersππππ and the temperature pressure lead to and dependent a temperature reduction material dependent in the material kinetic For = 3.044 and parametersd=0 a ,c the leadΟ binding to a Οreduc energytion in increases theπ π π π kineticdecreases ππππas energy the as magnetic ofthe the impurity electron field (d) while increases. the attractive We can see a significant decrease in the binding β Ο π π π π ππππ energyππππ (BE) . various confinements ( =donor3.044a 0 clear impurity, and decreasing we= have5.412 behavior inserted R ). The the asbinding thepressure temperatureenergy and again temperature energy dependent of thematerial electron while the attractive Ω‘Ω Ο π π π π β mentioned earlier. The same qualitative behavior can also be observed in Table 4 with 0 β coulombβ energy of the electron enhances. * * However,energy asthe d binding increases energy from d=0.1 a to d=0.5 a . For example, at = 3.044 and Ω‘Ω To see the effects of pressure0 strengthand temperatureΟ increases. parameters0π π π π This behavior on the persists binding for energy all d- values.of the shows a clear decreasingΟ behavior π π π π as the Οtemperature of the system increases.In F igThe.7a ,7b, the behavior of the donor binding energy had been shown as a function of β Ω‘Ω Ω‘Ω . different quantitative behavior for = 5.412 0* * = 2 the binding energy reducesβ significantly from 4.62499 ΟR to 2.55177π π π π R . at fixed value , Ω‘Ω donor impurity, we have inserteddecreases the aspressure the impurity and Intemperature (d) Fig increases..9a and 9dependent*b, We we can have see materialshow a significantn the effect decrease of changing in the the binding temperature0 dependence of the material parameters like the effective mass m (P,T) and dielectricthe magnetic field βstrength Ο , for differentπ π π π values of parameters : = c * To* see the* effectThisΟs of result pressureπ π π π is due and to temperature the great reduction parameters in theon coulombthe binding imp energyurity energy of the (Eq. 4), as we energy as d increases froofm the d=0.1 impurity a to position d=0.5 a(d=. For0.1 example,a )*, on the at binding = energy.3.044 Again,c and the binding energy 0 constant ( , ) on the temperature and pressure explainFig. 1. The groundin Table state energy1, where of the quantum m heterostructure for fixed valueΟ of magnetic field Ο β = * = * we haveΟ00* 5.412 insertedR against the the *numberpressure of and temperature dependent material Ω‘Ω ,strength (Οc ) 2 R and donorparabolic confinment strength impurity ππππ = 2 the binding energyshows great reduces enhancement significantly as we fromincrease 4.62499mentioned the magnetic ΟR earlier.to field2.55177 Thestrengthπ π π π Rsame. qualitative for fixed values behavior can also be observed in Table 4 with Ω‘Ω‘ .( *decreasesππππ andππππ ππππ increases with increasing T which diminishbasis fordonor a) donor impurity impurity at binding the origin (d = 0 a* ) and b) donor impurity at (d = 0.5 a β Fig. 2. The ground state energy of the quantum heterostructure for absence and presencec of c of the parameters: Temperature (T= 5,different 100, and quantitative 200K), Pressure behaviorΟ (P for=10 kbar)= 5 .and412 . ππππ ThisΟ resultπ π π π is due to the greatthe impurityreduction against in the the magnetic coulomb field strength impurity Οc the energydashed line(Eq. with 4), impurity as we and solid line energy (BE) . ππππ * for no impurity cases for Ο= 5.412 R . β Ω‘Ω 0 0 confinement frequencies = 3.044 and * = 5.412 R . We display inΟ figure 10 π π π π mentioned earlier. The same qualitativeFig. 3. The groundbehavior-state forcan fixed also value be of observed Οc = 2 R against in Table the distance 4 with for two Toβ see the effects ofβ pressure and temperature parameters on the binding energy of the Ο , Ο= 3.044 R0 ** dashed line and Ο= 5.412 0 R the solid line). In Fig.7a ,7b, the behavior of the donor binding energythe had donor been binding shown00 ( energyas a functionΟ against ofthe π π π π temperature0 Ο (T),) while the rest of the physical different quantitative behavior for = Fig.5.412 4. The ground. -state binding energy against Ο , where donor impurity,c we have inserted the pressure and temperature dependent material ( Ο= 3.044 R * for dashed line,β and Ο= 5.412 R * for solid line ) (a) d = 0 a* , (b) d = 0.1 a* , the magnetic field strength , for different parametersvalues0 of of0 parametersthe system are: kept0= fixed. The binding energy shows an important Ο π π π π and (c) d=0.5a* . To seec the effects of pressureFig. and5. The temperature binding energy forparameters d=0 a* at0 constant on the pressure binding (P=10 energykbar) as a functionof the of Ο for Ο dependence on the temperature,Ο and the impurity binding energy EB c decreases with three temperatures (5K, 100K, and 200K) for (a ) Ο= 3.044 R ** and b) Ο= 5.412 R . Ω‘Ω 00 donor impurity, we have insertedFig. 6. The bindingthe pressure energy change and for temperatured=0 a* at constant dependent pressure (P=10 material kbar) and Ο= 2 R * c Ω‘Ω‘ .increasing the temperature with respect to the temperature for( Ο= 5.412 R * 0 * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed (kbar) a Ω‘Ω temperature (20K) and for three different values of pressure (0, 10, and 20 ** Ο00= 3.044 Rb ) Ο= 5.412R . * Fig. 8. The variation of ground-state bindingFigure energy for8 d = 0 a against the pressure at fixed Ω‘Ω’ .( temperature (20K) and Ο= 2 R * for ( Ο= 3.044 R ** and Ο= 5.412R c 00 Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a
function of Οc and for three temperatures (5K, 100K, and 200K): ** a) Ο00= 3.044 R and b) Ο= 5.412 R . 384 * Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019 Fig. 10. The ground-state binding energy for d = 0.1 a at constant pressure (P=10 kba and * * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line * and Ο0 = 5.412 R for the solid line). * Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Fig. 12. The variation of ground-state binding energy for d=0.1a* as a function of the pressure * ** at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K). a) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 14. The binding energy for d=0.5 a at constant pressure (P=10 kbar) and Οc = 2 R against * * temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line).
Ω¨
) energy of the donor Hamiltonian enhances as the confinement strength ( increases energy of the donor Hamiltonian enhances as the confinement strength ( ) increases energy of the donor Hamiltonian enhances as the confinement strength ( ) increases * * 0 0 from 3.044 R to 5.412R . This energy behavior agrees with our expectation.Ο from 3.044 R* to 5.412R*. This energy behavior agrees with our expectation.Ο energy of the donor Hamiltonian enhances as the confinement strength ( ) increases 0 from 3.044 R* to 5.412R*. This energy behavior agrees with our expectation.Ο * * Ο0 Furthermore, we have investigated thefrom impurity 3.044 ground R to 5.412R -state eigenenergy. This energy (E) behavior and the agrees with our expectation. Furthermore, we have investigated the impurity ground -state eigenenergy (E) and the Furthermore, we have investigated the impurity ground -state eigenenergyparameters (E) and of the GaAs , ( ( , ) ( , ) ) , in the present calculations. In Fig. 5 binding energy (BE) against the magnetic field strength , for specific values of Furthermore, we have investigated the impurity ground -state eigenenergy (E)binding and the energy (BE) against the magneticβ field strength , for specific values of binding energy (BE) against the magnetic field strength , for specificto Fig.values16 , ofwe have shownππππ explicitlyππππ ππππ ππππππππππππ theβ behaviorππππ ππππ of the donor binding energy (BE) as a c 0 c 0 and versus values of (d). Fig.4a ,4b,4c,4d show the dependenceΟ s of the ground stateΟ and versus values of (d). Fig.4a ,4b,4c,4d show the dependenceΟ s of the ground stateΟ binding energy (BE) against the magnetic field strength , for specific valuesc of 0 and versus values of (d). Fig.4a ,4b,4c,4d show the dependenceΟ s of thfunctione ground of statetheΟ magnetic field strength , taking in consideration the impurity binding energy (BE) on the magnetic field strength , for different values of impurity c 0 and versus values of (d). Fig.4a ,4b,4c,4d show the dependenceΟ s of the groundbinding stateΟ energy (BE) on the magnetic field strength c, for different values of impurity binding energy (BE) on the magnetic field strength , for different valuesposition of impurity (d), temperature (T), pressure (P) andΟ confinement frequency . Fig. 5a, 5b Οc c distances : (a) d=0 , (b) d=0.1 , and (c) d=0.5 and two confinement frequencies distances : (a) d=0 , (b) d=0.1 , and (c) d=0.5 Ο and two confinement frequencies0 binding energy (BE) on the magnetic field strength , for different valuesc of impurity show the donor binding energies against the magnetic field strength forΟ three different β β β distances : (a) d=0 , (b) d=0.1 , and (c) d=0.5 Ο and two confinement frequenciesβ β β * ππππ *ππππ ππππ * * ( =3.044 R and =energy5.412R of). theThe donor binding Hamiltonianenergy energy of (BE the enhances ),donor against Hamiltonian as the the magnetic confinementβ enhances field strength asβ cthe confinement( ) increasesβ strength ( ( = )3.044 increases R and ππππ =5.412R )ππππ. The binding energyππππ (BE), against the magnetic field distances : (a) d=0 , (b) d=0.1 , and (c) d=0.5 Ο and two confinement frequencies temperatures (5K, 100K, and 200K) and fixed values of pressure, impurity position ( =3.044 R* and ππππ =5.412R*)ππππ. The binding energyππππ (BE), against the magnetic field ππππ0 ππππ0 * * *β * β β 0 0 0 0 strength, is greatly reducedfrom as 3.044the distances R to 5.412R (d)from increases. This3.044* energy Ras shownto 5.412Rbehavior by F*. ig Thisagreess. 2, energy 3 with and ourbehavior4. expectation. agreesΟ with our expectation.strengthππππΟ , is greatly reducedππππ as the distances (d) increases as shown by Figs. 2, 3 and 4. ( =3.044 R and 0ππππ =5.412R )ππππ. The0 binding energyππππ (BE), against the magnetic field d=0 and confinement frequency = 3.044 R . For fixed temperature, the figure strengthππππ , is greatly reducedππππ as the distances (d) increases as shown by Figs. 2, 3 and 4. β β In addition, the figures demonstrate that the0 binding energy 0increases as magnetic field 0 strengthππππ , is greatly reducedππππ as the distances (d) increases as shown by Figs. 2,In 3 addition,and 4. clearly theππππ figures shows demonstrate the enhancement that the of bindingtheΟ binding energy energy increases as the as magnetic magnetic field field strength Furthermore, we haveFurthermore, investigatedIn addition, we the have impurity the investigated figures ground demonstrate -thestate impurity eigenenergy that ground the binding(E) -state and energyeigenenergythe increases (E) asand magnetic the field and the parabolic confinement strengths increase. In addition, the figures demonstrate that the binding energy increases as magnetic and field the parabolic increases. confinement This enhancement strength ins the idonorncrease. binding energy can be attributed to the binding energy (BE) bindingagainst theenergy magnetic (BE) againstfield strength the magnetic , for field specific strength values of, for specific values of c 0 and the parabolic confinement strengths increase. Ο ππππ Οc c ππππ0 and the parabolic confinement strengths c increase. c 0 Ο 0 In Table 3, we haveand listedversus the values donor of impurityand (d) . versusFig .energy4Οa valuesc,4b,4c,4d and of binding (d)show. Fig theenergy.4a dependence,4b,4c,4dΟ as a shows of ththee groundππππdependence0 Ο stateΟ s of the groundIn Tableparabolic stateΟ 3, wemagnetic have listedconfinement the donor term impurity energyin Eq. (3).and For binding fixed energyvalues ofas magnetica In Table 3, we have listed the donor impurity energy and binding energy as a 1 2 2 c 0 4 function of magnetic fieldbinding strength energy Οfor (B E ) bindingon= the3.044 magnetic energy and ( Bfield forE) on variousstrength the magnetic values , for ofππππ field differentd. strength values , offor impurity different values of impurityfield strength , the binding energy ΟdecreasesΟ when the temperature increases, as In Table 3, we have listed the donor impurity energy and binding energyfunction as a of magnetic field strength for = 3.044 and for various values of d. functionβ of magnetic field strength for = 3.044 and for various values of d. β c 0 c c c For = 3.044 and d=0 a*, theΟ bindingΟ energy increasesπ π π π as the magneticΟ field Ο clearly shown Οin Fig.5*a. Similarc behavior0 of the donor binding energy is displayed in distances : (a) d=0 distance, (b) d=0.1s : (a), d=0and (c), (b)d=0.5 d=0.1 andS. ,Abuzaid twoand= (c)confinement3 et.044 d=0.5 al. and frequencies two confinement β For frequencies= 3.044 and d=0 a , theΟ bindingΟ energy increasesπ π π π as the magnetic field function of magnetic field strength for * c and0 for various values of d. β β For β = 3β.044 andβ βd=0 a , theΟ bindingβΟ energy increasesπ π π π as the magneticβ field Ο0 π π π π * * * * β 0 Fig.5b for different, = 5.412 . strength increases. This behavior( =3.044 persists R and for ππππall( =d-5.412R=values.3.044 )However,ππππR. The and binding ππππ the=*5.412R binding energyβ ππππc )ππππ .(BEenergy The0), bindingagainst energytheππππ magnetic (BE), fieldagainst thestrength magneticΟ increases. field π π π π This behavior persists for all d-values. However, the binding energy For = 3.044 and0 d=0 a , theΟ bindingΟ energy increasesπ π π π as the magnetic field strengthΟ increases.π π π π This behavior persists for all d-values. However, the binding energy β 0coulomb energy 0of0 the electronβ enhances.0 the impurity binding energy E decreases with Ο0 π π π π decreases as the impuritystrength (d)ππππ increases., is greatly We canreducedππππ0strengthππππ see a assignificant, isthe greatly distances decrease reducedππππ (d) increases inas thethe bindingdistances as shown (d) by increases Figs. 2, as3 andshown 4. by Figs. 2, 3B and 4. strengthΟ increases.π π π π This behavior persists for all d-values. However, the bindingdecreases energy as the impurityIn Fig.6 (d)we increases.have shown We the can dependence see a significant of the decrease donor binding in the bindingenergy on the In Fig.9a and 9b, wedecreases have shown as the impurity the effect (d) increases.increasing We can the see temperature. a significant decrease in the binding * * energy as d increases froInm addition,d=0.1of changing a theto d=0.5figures theIn a temperature,demonstrateaddition,. For example, the thatfigures atat the fixed bindingdemonstrate= 3 . value044 energy that andof increases the bindingIn asFig. magnetic energy 11a and increases field 11b, theasenergy magnetic pressure as d fieldincreases effect onfro them d=0.1 a* to d=0.5 a*. For example, at = 3.044 and decreases as the impurity (d) increases. We can see a significant decrease in the binding temperature* for fixed values of pressure (P=10 Kbar), = 2 , = 0 and the impurity position (d= 0.1 a*), on the bindingβ donor* binding* energy for d=0.1 =a3 .044 against the energy as d increases0 from d=0.1 a to d=0.5 a . For example, at and β β β Ο * π π π π * c0 = 2 the binding energy energy.and reduces the parabolic Again, significantly theconfinement and binding fromthe parabolic strength 4.62499 energy sconfinement R shows to i ncrease.*2.55177 great strength R .* smagnetic increase. field strength = had2 been the binding illustrated.β energy reduces significantly from 4.62499 ΟR* to 2.55177π π π π π π π π ππππ R*. ππππ energy as d increases from d=0.1 a to d=0.5 a . For example, at = 3.044 and0 various confinements ( = 3.044 and = 5.412 R ). The binding energy again β = 2 Ο * π π π π * c enhancement as we increase the the magnetic binding energy field reducesFig. 11a significantly obviously fromshows 4.62499 that theR β tobinding 2.55177 energy R . β β Ο π π π π c c 0 0 c β 0 0 This result is due to the greatΟ reduction in the Οcoulomb impurity energyβ ππππ (Eq. 4), as we ππππ 0* ThisΟ result*π π π π is due to the great reductionΟ in theπ π π π coulombΟ impurity energy (Eq. 4), as we strength = for2 fixed the binding valuesc energy of the reduces parameters: significantly increases from 4.62499 as the Ο Rmagnetic to 2.55177 π π π π field R . strengthshows a clearenhances decreasing behavior as the temperature of the system increases. The In Table 3, we have Inlisted ThisΟTable theresult 3 donorπ π π π , we is duehave impurity to listed the energygreat the donor reduction and impuritybinding in the energyenergy coulomb asand a imp bindingurity energyenergy (Eq.as a 4), as we Temperature (T= 5,β 100, and 200K), Pressure (P=10 while the pressure (0, 10, and 20 kbar), T, d, and mentioned earlier. The same qualitative behaviorc can also be observed in Table 4 with mentioneddependence earlier. The of same the materialqualitative parameter behaviors likecan thealso effective be observed mass inm *Table(P,T) 4and with dielectric ThisΟ resultπ π π π is due to the great reduction= 3.044 in the coulomb = imp3.044urity energy (Eq. 4), as we functionkbar) of and magnetic confinement functionfield strength offrequenciesmentioned magnetic for earlier. field strength The same andqualitative for for various behavior values andcan are of alsofor d. fixed. various be observed Fig. values in 11bof Table d. shows 4 with similar β β * different quantitative behaviorand for = 5.412 . We display inc Fig. 100 the donor c behavior0 of the (BE) but differentfor different quantitativeconstant confinement (behavior, ) on for the temperature= 5.412 and. pressure explain in Table 1, where m mentioned earlier. *TheΟ same qualitativeΟ * behaviorπ π π π Ο canΟ also be observedπ π π π in Table 4 with For = 3.044 andForβ d=0 =a3, .044the binding and d=0energy a , increasesthe binding as =energythe5 .magnetic412 increases field as the magnetic field binding0 energy against thedifferent temperature quantitative (T), behavior while for . Effective-mass approximation β β β ππππ 0 Ο π π π π β decreases* ππππ andππππ ππππ increasesΟ with increasingπ π π π T which diminish donor impurity binding the0 rest ofdifferent the physical quantitative0 parameters behavior offor the =system5.412 . investigates the pressure effects on m and , To see the effects of pressurestrength Οand increases. temperatureπ π π π Thisstrength parameters behaviorΟ increases. persistson theπ π π π Thisbinding for allbehavior denergy-values. persists of However, the forΟ all0 the d- values.bindingπ π π π However, energy theTo binding see the energy effects of pressure and temperature parameters on the binding energy of the are kept fixed. The binding energy shows an β as shown in Table 1 which explain the reason ππππof To see the effects of0 pressure and temperature parameters on the bindingenergy energy (B Eof) . the ππππ donor impurity, we havedecreases insertedimportant as the the pressure dependenceimpuritydecreases and(d) increases. temperature onas the the impurity temperature,We dependentcan (d) Οsee increases. a significant material and π π π π We decreaseenhancingcan see a in significant theBE. binding decrease in the binding To see the effects of pressure and temperature parameters on the binding energydonor of theimpurity, we have inserted the pressure and temperature dependent material donor impurity, we have inserted the pressure and temperature dependent material * * * * = 3.044 = 3.044 In Fig.7a ,7b, the behavior of the donor binding energy had been shown as a function of energy as d increasesdonor impurity,energy from d=0.1as wed increases ahaveto d=0.5inserted fro ma .d=0.1 theFor pressureexample, a to d=0.5 and at atemperature. For example, dependentand at material and β β 0 0 Ω‘Ω = :Ω‘Ω the binding energy= 2 reduces the binding significantly energy reducesfrom 4.62499 significantly ΟR* to from2.55177 π π π π 4.62499 R*. ΟR* to 2.55177π π π π the Rmagnetic*. field strength , for different values of parameters 2 = Ω‘Ω β β c 0 c c Ο Ο Ω‘Ω 4), as we .ThisΟ resultπ π π π is due to theThisΟ great resultπ π π π reduction is due to in the the great coulomb reduction impurity in the energy coulomb (Eq. imp4), urityas we energy (Eq Ω‘Ω‘ mentioned earlier. Thementioned same qualitative earlier. Thebehavior same canqualitative also be behaviorobserved canin Table also be4 withobserved in Table 4 with different quantitative differentbehavior quantitativefor = 5. 412behavior . for = 5.412 . β β Ο0 π π π π Ο0 π π π π To see the effects of Topressure see the and effect temperatures of pressure parameters and temperature on the binding parameters energy on of the the binding energy of the
donor impurity, we donorhave insertedimpurity, the we pressure have inserted and temperature the pressure dependent and temperature material dependent material
Ω‘Ω Ω‘Ω
Fig. 9.a Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * strength (Οc )= 2 R and parabolic confinment strength Ο0 = 5.412 R against the number of basis for a) donor impurity at the origin (d = 0 a* ) and b) donor impurity at (d = 0.5 a* ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of
the impurity against the magnetic field strength Οc the dashed line with impurity and solid line * for no impurity cases for Ο0 = 5.412 R . * Fig. 3. The ground-state for fixed value of Οc = 2 R against the distance for two ** Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line).
Fig. 4. The ground-state binding energy against Οc , where * * * * ( Ο0 = 3.044 R for dashed line, and Ο0 = 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , and (c) d=0.5a* . * Fig. 5. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * Fig. 9.b ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). * Fig. 9. The ground-state binding energy forFigure d=0.1 a 9 at constant pressure (P=10 kbar) as a function of Οc and for three temperatures (5K, 100K, and 200K): ** a) Ο00= 3.044 R and b) Ο= 5.412 R . Fig. 10. The ground-state binding energy for d = 0.1 a* at constant pressure (P=10 kba and * * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line * and Ο0 = 5.412 R for the solid line). Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019 * 385 Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Ω© Fig. 12. The variation of ground-state binding energy for d=0.1a* as a function of the pressure * ** at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K). a) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 14. The binding energy for d=0.5 a at constant pressure (P=10 kbar) and Οc = 2 R against * * temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line). Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * strength (Οc )= 2 R and parabolic confinment strength Ο0 = 5.412 R against the number of basis for a) donor impurity at the originS. Abuzaid (d = 0 a* et) and al. b) donor impurity at (d = 0.5 a* ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of
the impurity against the magnetic field strength Οc the dashed line with impurity and solid line * for no impurity cases for Ο0 = 5.412 R . * Fig. 3. The ground-state for fixed value of Οc = 2 R against the distance for two ** Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line).
Fig. 4. The ground-state binding energy against Οc , where * * * * ( Ο0 = 3.044 R for dashed line, and Ο0 = 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , and (c) d=0.5a* . * Fig. 5. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a
function of Οc and for three temperatures (5K, 100K, and 200K): a) Ο= 3.044 R ** and b) Ο= 5.412 R . 00 Fig. 10. The ground-state binding energy for d = 0.1 a* at constant pressure (P=10 kba and * Figure 10 * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line * and Ο0 = 5.412 R for the solid line). * Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Fig. 12. The variation of ground-state binding energy for d=0.1a* as a function of the pressure * ** at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K). a) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 14. The binding energy for d=0.5 a at constant pressure (P=10 kbar) and Οc = 2 R against * * temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line).
Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * strength (Οc )= 2 R and parabolic confinment strength Ο0 = 5.412 R against the number of basis for a) donor impurity at the origin (d = 0 a* ) and b) donor impurity at (d = 0.5 a* ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of
the impurity against the magnetic field strength Οc the dashed line with impurity and solid line * for no impurity cases for Ο0 = 5.412 R . * Fig. 3. The ground-state for fixed value of Οc = 2 R against the distance for two ** Ο00 , ( Ο= 3.044 R dashed line Fig.and 11.a Ο0 = 5.412 R ) the solid line).
Fig. 4. The ground-state binding energy against Οc , where ( Ο= 3.044 R * for dashed line, and Ο= 5.412 R * for solid line ) (a) d = 0 a* , (b) d = 0.1 a* , Ω‘Ω 0 0 * and (c) d=0.5a . * Fig. 5. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a
function of Οc and for three temperatures (5K, 100K, and 200K): ** a) Ο00= 3.044 R and b) Ο= 5.412 R . Fig. 10. The ground-state binding energy for d = 0.1 a* at constant pressure (P=10 kba and * * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line Fig.* 11.b and Ο= 5.412 R for the solid line). 0 Fig. 11. The variation of binding energy for d=0.1a* against the Ο at fixed temperature (20K) Figure 11 c ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Fig. 12. The variation of ground-state binding energy for d=0.1a* as a function of the pressure * ** at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for 386 **Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019 three temperatures (5K, 100K, and 200K). a) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 14. The binding energy for d=0.5 a at constant pressure (P=10 kbar) and Οc = 2 R against * * Ω‘Ω‘ .(temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line
Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * strength (Οc )= 2 R and parabolic confinment strength Ο0 = 5.412 R against the number of basis for a) donor impurity at the origin (d = 0 a* ) and b) donor impurity at (d = 0.5 a* ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of
the impurity against the magnetic field strength Οc the dashed line with impurity and solid line * for no impurity cases for Ο0 = 5.412 R . * Fig. 3. The ground-state for fixed value of Οc = 2 R against the distance for two ** Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line). S. Abuzaid et al. Fig. 4. The ground-state binding energy against Οc , where * * * * ( Ο0 = 3.044 R for dashed line, and Ο0 = 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , and (c) d=0.5a* . * Fig. 5. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a
function of Οc and for three temperatures (5K, 100K, and 200K): ** a) Ο00= 3.044 R and b) Ο= 5.412 R . Fig. 10. The ground-state binding energy for d = 0.1 a* at constant pressure (P=10 kba and * * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line * and Ο0 = 5.412 R for the solid line). * Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . * Fig. 12. The variation of ground-state bindingFigure energy 12 for d=0.1a as a function of the pressure at fixed temperature (20K) and Ο= 2 R * for Ο= 3.044 R ** and Ο= 5.412 R . energy of the donor Hamiltonian enhances as thec confinement00 strength ( ) increases * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for three temperatures (5K, 100K, and 200K). a) Ο= 3.044 R ** and b) Ο= 5.412 R0 . from 3.044 R* to 5.412R*. This energy behavior agrees with00 our expectation.Ο parameters of GaAs , ( ( , ) ( , ) ) , in the present calculations. In Fig. 5 Fig. 14. The binding energy for d=0.5 a* at constant pressure (P=10 kbar) and Ο= 2 R * against c β temperature for( Ο= 3.044 R* for the dashed line and for Ο= 5.412 R * solid line). 0 0 to Fig.16 , we have shownππππ explicitlyππππ ππππ ππππππππππππ theβ behaviorππππ ππππ of the donor binding energy (BE) as a Furthermore, we have investigated the impurity ground -state eigenenergy (E) and the function of the magnetic field strength , taking in consideration the impurity Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * binding energy (BEstrength) against(Ο ) =the 2 R andmagnetic parabolic confinment strength field strength Ο =, 5.412 for Rspecificagainst the values number ofof c 0 c * * Ο basis for a) donor impurity at the origin (d = 0 a ) and cb) donor impurity at (d position= 0.5 a ). (d),0 temperature (T), pressure (P) and confinement frequency . Fig. 5a, 5b and versus values Fig.of 2(d). The. groundFig.4 astate ,4b,4c,4d energy of the show quantum the heterostructure dependenceΟ fors absence of th ande ground presence ofstate Ο the impurity against the magnetic field strength Ο the dashed line with impurity and solid line 0 c show the donor binding energies against the magnetic field strength forΟ three different for no impurity cases for Ο= 5.412 R * . binding energy (BE) on the magnetic field strength , for0 different values of impurity Fig. 3. The ground-state for fixed value of Ο= 2 R * against the distance for two c temperatures (5K, 100K, and 200K) and fixed values of pressure, impurity position Ο , Ο= 3.044 R** dashed line andc Ο= 5.412 R the solid line). distances : (a) d=0 , (b) d=0.100( , and (c) d=0.5 Ο and0 two confinement) frequencies Fig. 4. The ground-state binding energy against Ο , where β β β c d=0 and confinement frequency = 3.044 R . For fixed temperature, the figure ( Ο= 3.044 R * for dashed line, and Ο= 5.412 R * for solid line ) (a) d = 0 a* , (b) d = 0.1 a* , = * 0ππππ = *ππππ 0 ππππ ( 3.044 R and 5.412R ). The binding energy (BE* ), against the magneticβ field β and (c) d=0.5a . 0 energy of the donor Hamiltonian enhances as the confinement strength ( * ) increases clearlyππππ shows the enhancement of theΟ binding energy as the magnetic field strength 0 Fig. 50. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for strengthππππ , is greatly reducedππππ as the distances (d) increases as shown** by Figs. 2, 3 and 4 . three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . * * 0 Fig. 13.a Ο * * from 3.044 R to 5.412R . This energy behavior agreesFig. 6. withThe binding our energyexpectation. change for d=0 a at constant pressure (P=10 kbar) and Οcincreases.= 2 R This enhancement in the donor binding energy can be attributed to the In addition, the figures demonstratewith thatrespect the to thebinding temperature energy for( Οincreases= 5.412 R * as magnetic field 0 c = * Ο solid line and for Ο0 3.044 R for the dashed line ). . parabolic magnetic confinement term in Eq. (3). For fixed values of magnetic Furthermore, we have investigated andthe theimpurity parabolic ground Fig.confinement 7 .- Thestate variation eigenenergy strength of grounds-state (E) binding andincrease. energythe for d=0a* against the Ο at fixed 1 2 2 Ω‘Ω’ c temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) c 0 4 Ο Ο ** field strength , the binding energy decreases when the temperature increases, as binding energy (BE) against theΟ magnetic field strength , for specific Ο00 =values 3.044 ππππ Rb of ) Ο = 5.412R . In Table 3, Fig.we 8. haveThe va riationlisted of theground donor-state binding impurity energy energy for d = 0 aand* against binding the pressure energy at fixed as a c temperaturec (20K) and Ο= 2 R * for ( Ο0= 3.044 R ** and Ο= 5.412R ). Ο and versus values of (d)In. FigFig.114aa ,4b,4c,4dand 11b, theshow pressure the dependence effectΟ on thes donorof th ebinding cground energy stateΟ00 for d=0.1 against clearly shown in Fig.5a. Similar behavior of the donor binding energy is displayed in Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a function of magnetic field strength for = 3.044 and forβ various values of d. function of Ο and for three temperatures (5K, 100K, and 200K): binding energy (BE) on the magnetic fieldfield strengthstrength had, for been different illustrated valuesc . Fig.11 of impuritya obviously β showsππππ that the Fig.5b for different, = 5.412 . a) c Ο= 3.044 0 R ** and b) Ο= 5.412 R . = 3.044 * Ο 00Ο π π π π For and d=0 a , the binding energy increases* as the magnetic field β Fig.c c 10. The ground-state binding energy for d = 0.1 a at constant pressure (P=10 kba and 0 binding energy increases as Οβthe magnetic field *strength enhances while the *pressure (0, Ο π π π π distances : (a) d=0 , (b) d=0.1 , and (c) d=0.5 Ο and two Οconfinement= 2 R , and temperature frequencies for (Ο = 3.044 R dashed line 0 c 0 In Fig.6 we have shown the dependence of the donor binding energy on the β strengthβ Ο increases.π π π π Thisβ behavior persists for all d-values.* However, the binding energy and Ο0 = 5.412 R for the solid line). * ππππ 10, and 20*ππππ kbar), T, d, and ππππ = 3.044 are fixed. Fig.11b shows* similar behavior of ( =3.044 R and =5.412R ). The binding energyFig. 11. The(BE variation), against of binding the energymagnetic for d=0.1 fielda against the Οc at fixed temperature (20K) decreases as the impurity (d) increases.β We can see a significant decrease** intemperature the binding for fixed values of pressure (P=10 Kbar), = 2 , = 0 and for0 three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . 0 0 the (BE) but for different confinementΟ π π π π = 5.412 . Effective-mass approximation* β β strengthππππ , is greatly reducedππππ as the distances (d) increasesFig. 12. The as variation shown of ground by F-igstates. binding2, 3 and energy 4. for d=0.1a as a function of the pressure c * β *Fig.13.b* ** ( = 3.044 and = 5.412 R )Ο π π π π ππππ ππππ energy as d increases froat fixedm d=0.1 temperature a to (20K) d=0.5 and Ο ac =.2 RFor for example, Ο00= 3.044 R at and Ο == 5.412 R3various.044. confinementsand . The binding energy again * 0 investigates the pressure effects on m andΟ , as shownπ π π π * in Table 1 which explain the Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οcβ for β β In addition, the figures demonstrate that the binding energy increases as magneticFigure field 13 0 0 0 *** * Ο π π π π Ο = 2 three temperatures (5K, 100K, and 200K). a) Ο00= 3.044 R and b) ΟΟ = 5.412 Rshows .π π π π a clear decreasing behavior as the temperature of the system increases. The the binding energy reducesππππππππ significantly from 4.62499 R to 2.55177 R . reason of enhancing BE. Fig. 14. The binding energy for d=0.5 a* at constant pressure (P=10 kbar) and Ο= 2 R * against and the parabolic confinement strengthβs increase. c c temperature for( Ο= 3.044 R* for the dashed line and for Ο= 5.412 R * solid line). * ThisΟ resultπ π π π is due to the great reduction0 in the coulomb impurity energy0 (Eq.dependence 4), as we of the material parameters like the effective mass m (P,T) and dielectric c In Fig. 12, the 0 ground state binding energy had been plotted . The binding energy, (BE) shows Ο In Fig.12, the ground ππππstate binding energy as a function of the pressure for fixed values , In Table 3, we haveas listed a mentioned function the donor earlier. ofimpurity theThe sameenergy pressure qualitative and forbinding behavior fixed energy values can as alsoa great be observed enhancement in Tableconstant as 4 the with pressure( , ) on increases the temperature for and pressure explain in Table 1, where m* ofof T=20K, d = 0.1 , = 2 , andand atat differentdifferent confinements:fixed values of =confinement frequency because of ππππ Ω‘Ω£andππππ ππππ increases with increasing T which diminish donor impurity binding function of magnetic field strengthdifferent for quantitative =β 3.044 behavior βand for for various= 5.412 values . of d. * decreasesππππ confinements: c and increasing m and0 decreasing . This effective 3.044 and = 5.412ππππ R Ο had beenπ π π π β plotted . The binding βenergy, (BE), shows a Οgreat c 0 ππππ For = 3.044 and d=0 aβ*, theΟ bindingΟ energyβ increasesπ π π π asΟ 0the magneticπ π π π field energy (BE) . ππππ π π π π Ο0 β enhancementTo see as the the effect pressures of pressureincreases and for temperature fixed values parameters of confinement on the frequencybinding energy of the 0 Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019 387 strengthΟ increases.π π π π This behavior persists for all d-values. However, the binding energy becausedonor of increasing impurity, m * weand have decreasing inserted the . pressureThis effective and temperaturemass and dielectric dependent In Fmaterialig.7a ,7b , the behavior of the donor binding energy had been shown as a function of decreases as the impurity (d) increases. We can see a significant decreaseππππ in the binding pressure dependence lead to lower the electron kineticππππ energy while the coulomb energy the magnetic field strength , for different values of parameters : = * * = 3.044 c 0 Ω‘Ω energy as d increases froincreases.m d=0.1 a to d=0.5 a . For example, at and β Ο Ο 0 = 2 the binding energy reduces significantly from 4.62499 ΟR* to 2.55177π π π π R*. Ω‘Ω‘ β Fig.13a and 13b, the binding energy as a function of magnetic field strength for d=0.5 c ThisΟ resultπ π π π is due to the great reduction in the coulomb impurity energy (Eq. 4), as we β and various confinement, had been shown. We have plotted in Fig.14 the dependence ππππof mentioned earlier. The same qualitative behavior can also be observed in Table 4 with the donor binding energy against the temperature for d=0.5 and various confinement different quantitative behavior for = 5.412 . β frequencies = 3.044 and = 5.412 R and the restππππ parameter are fixed. The β 0 β β ΟΟ0 π π π π π π π π Ο0 To see the effects of pressurebehavior and is temperaturein qualitative parametersagreement with on thethe bindingresults expl energyained ofin Fig.the 6. donor impurity, we have insertedIn F igthe.15 apressure and 15b, andwe showtemperature similar qualitativedependent behaviormaterials as given in figures
3.10 a and b (d=0 a*). Fig.15a and 15b show the effect of pressure and impurity position
comparison between Ω‘Ω d=0.5 ) on the (BE) as a function of magnetic field strength. The) β two d-valuesππππ (d=0 and 0.5 a*) show that, as we increase, d, the binding energy increases
Ω‘Ω£
Fig. 1. The ground state energy of the quantum heterostructure for fixed value of magnetic field * * strength (Οc )= 2 R and parabolic confinment strength Ο0 = 5.412 R against the number of basis for a) donor impurity at the origin (d = 0 a* ) and b) donor impurity at (d = 0.5 a* ). Fig. 2. The ground state energy of the quantum heterostructure for absence and presence of
the impurity against the magnetic field strength Οc the dashed line with impurity and solid line * for no impurity cases for Ο0 = 5.412 R . * Fig. 3. The ground-state for fixed value of Οc = 2 R against the distance for two ** Ο00 , ( Ο= 3.044 R dashed line and Ο0 = 5.412 R ) the solid line).
Fig. 4. The ground-state binding energy against Οc , where * * * * ( Ο0 = 3.044 R for dashed line, and Ο0 = 5.412 R for solid line ) (a) d = 0 a , (b) d = 0.1 a , and (c) d=0.5a* . * Fig. 5. The binding energy for d=0 a at constant pressure (P=10 kbar) as a function of Οc for ** three temperatures (5K, 100K, and 200K) for (a ) Ο00= 3.044 R and b) Ο= 5.412 R . S. Abuzaid* et al. * Fig. 6. The binding energy change for d=0 a at constant pressure (P=10 kbar) and Οc = 2 R * with respect to the temperature for( Ο0 = 5.412 R * solid line and for Ο0 = 3.044 R for the dashed line ). . * Fig. 7. The variation of ground-state binding energy for d=0a against the Οc at fixed temperature (20K) and for three different values of pressure (0, 10, and 20 kbar) a) ** Ο00= 3.044 Rb ) Ο= 5.412R . Fig. 8. The variation of ground-state binding energy for d = 0 a* against the pressure at fixed * ** temperature (20K) and Οc = 2 R for ( Ο00= 3.044 R and Ο= 5.412R ). Fig. 9. The ground-state binding energy for d=0.1a* at constant pressure (P=10 kbar) as a
function of Οc and for three temperatures (5K, 100K, and 200K): ** a) Ο00= 3.044 R and b) Ο= 5.412 R . Fig. 10. The ground-state binding energy for d = 0.1 a* at constant pressure (P=10 kba and * * Οc = 2 R , and temperature for (Ο0 = 3.044 R dashed line * and Ο0 = 5.412 R for the solid line). * Fig. 11. The variation of binding energy for d=0.1a against the Οc at fixed temperature (20K) ** for three pressure values (0, 10, and 20 kbar) a) for Ο00= 5.412 Rb ) and for Ο= 3.044 R . Fig. 12. The variation of ground-state binding energy for d=0.1a* as a function of the pressure * ** at fixed temperature (20K) and Οc = 2 R for Ο00= 3.044 R and Ο= 5.412 R . * Fig. 13. The binding energy for d=0.5a at constant pressure (P=10 kbar) as a function of Οc for three temperatures (5K, 100K, and 200K). a) Ο= 3.044 R ** and b) Ο= 5.412 R . 00 * = * Fig. 14. The binding energy for d=0.5 a at constantFigure pressure 14 (P=10 kbar) and Οc 2 R against * * temperature for( Ο0 = 3.044 R for the dashed line and for Ο0 = 5.412 R solid line).
Fig. 15.a
Ω‘Ω€
Fig. 15.b
* Fig. 15. The binding energy for d=0.5a againstFigure the 15 Οc at fixed temperature (20 K) for three ** pressure values (0, 10, and 20 kbar): a) for ( Ο00= 3.044 Rb ) and Ο= 5.412 R ). Fig. 16. The variation of ground-state binding energy for d = 0.5 a* against the pressure at fixed ** temperature (20K) and Ο2c = for Ο00= 3.044 R and Ο= 5.412 R . * mass and dielectricTable pressure 1. The dependence dependence of the physical lead parameters function on the pressure of and magnetic temperature. field strength for d=0.5a to lower the electronTable 2 . The kinetic ground state energy (m=0) energy while (in R*) the computedand by various the exact confinement, diagonalization method had been shown. We 1 against expansion method for various range of magnetic field strength (1Ξ³ = 6.75B (Tesla)). the dependence of the Ω‘Ω₯ coulomb energy increases.N have plotted in Fig. 14 Fig. 13a and 13b,Table 3 the. The donor binding impurity energy ground state as aenergy (E(donorR*), and bindingdonor impurity energy binding againstenergy the temperature * (BE(R )) against the magnetic field strength Οc and various impurity position (d) for * Ο0 = 3.044 R . 388 Table 4. The donor impurity energy (E(R*), and donor impurity bindingInt. J. Nanoenergy Dimens., (BE(R*)) against 10 (4): 375-390, Autumn 2019 * the magnetic field strength Οc and various impurity position (d) for Ο0 = 5.412 R . energy of the donor Hamiltonian enhances as the confinement strength ( ) increases
0 from 3.044 R* to 5.412R*. This energy behavior agrees with our expectation.Ο
Furthermore, we have investigated the impurity ground -state eigenenergy (E) and the
binding energy (BE) against the magnetic field strength , for specific values of
c 0 and versus values of (d). Fig.4a ,4b,4c,4d show the dependenceΟ s of the ground stateΟ
binding energy (BE) on the magnetic field strength , for different values of impurity
c distances : (a) d=0 , (b) d=0.1 , and (c) d=0.5 Ο and two confinement frequencies β β β ( =3.044 R* and ππππ =5.412R*)ππππ. The binding energyππππ (BE), against the magnetic field S. Abuzaid et al. energy of the donor Hamiltonian enhances0 as the confinement0 strength ( ) increases strengthππππ , is greatly reducedππππ as the distances (d) increases as shown by Figs. 2, 3 and 4. 0 from 3.044 R* to 5.412R*. This energy behavior agrees with our expectation.Ο In addition, the figures demonstrate that the binding energy increases as magnetic field
Furthermore, we have investigated the and impurity the parabolic ground confinement -state eigenenergy strengths (E) and increase. the binding energy (BE) against the Οmagneticc field strength , for specific valuesππππ0 of In Table 3, we have listed the donor impurity energy and binding energy as a c 0 and versus values of (d). Fig.4a ,4b,4c,4d show the dependenceΟ s of the ground stateΟ function of magnetic field strength for = 3.044 and for various values of d. β binding energy (BE) on the magnetic field strength , for different valuesc of0 impurity For = 3.044 and d=0 a*, theΟ bindingΟ energy increasesπ π π π as the magnetic field c Οβ distances : (a) d=0 , (b) d=0.1 , and0 (c) d=0.5 and two confinement frequencies β strengthβ Ο increases.π π π π Thisβ behavior persists for all d-values. However, the binding energy ( =3.044 R* and ππππ =5.412R*)ππππ. The binding energyππππ (BE), against the magnetic field decreases as the impurity (d) increases. We can see a significant decrease in the binding 0 0 strengthππππ , is greatly reducedππππ as the distances (d) increases as shown by Figs. 2, 3 and 4. * * energy as d increases from d=0.1 a to d=0.5 a . For example,* at = 3.044 and Fig. 15. The binding energy for d=0.5a against the Οc at fixed temperature (20 K) for three In addition, the figures demonstrate that the binding energy increasespressure as magnetic values (0, field 10, and 20 kbar): a) for ( Ο= 3.044 Rb**β ) and Ο= 5.412 R ). 0* 00* = 2 the binding energy reduces significantly from 4.62499 ΟR to 2.55177π π π π * R . Fig. 16. The variation of ground-state bindingFigure energy 16 for d = 0.5 a against the pressure at fixed and the parabolic confinement strengthsβ increase. temperature (20K) and Ο2= for Ο = 3.044 R ** and Ο= 5.412 R . Οc π π π π c 00 This result is due to the great reductionTable 1. Thein thedependence coulomb of theimp physicalurity energyparameters (Eq. on 4),the pressureas we and temperature. c 0 Ο ππππ Table 2. The ground state (m=0) energy (in R*) computed by the exact diagonalization method
In Table 3, we have listedmentioned the donor earlier. impurity The energy same qualitativeand binding1 behavior energy canas aalso be observed in Table 4 with * against expansion method for various range of magneticincrease field the strength temperature (1Ξ³ = 6.75B (Tesla)). from T=5K to T= 200 K for d=0.5 a and variousN confinement frequencies * * ,respectively* calculated at Οc =2.0 R , Ο = 5.412 R function of magnetic field strengthdifferent for quantitative = 3.044 behavior and forforTable various 3=. The5. 412donor values impurity . of d. ground state energy (E(R ), and donor impurity binding energy 0 and * and the rest (BE(R )) against the magnetic field strength Οandc and various pressure impurity P=10 position Kbar.Also (d) for the donor impurity parameter areβ fixed. The behaviorβ is in qualitative * c 0 0 = * For = 3.044 and d=0 a , theΟ bindingΟ energy increasesπ π π π asΟ the magneticπ π π π field Ο0 3.044 Rbinding. energy is increasing function of pressure
To see the agreementeffects of pressure with the andTable results temperature 4. The donorexplained impurity parameters in energy Fig. on (E6.( Rthe*), and binding donor impurityenergy bindingof the energy (BE(R*)) against β for fixed values of temperature and magnetic 0 In Fig. 15a and 15b, the we magnetic show field similar strength qualitative Ο and various impurity position (d) for Ο= 5.412 R * . strengthΟ increases.π π π π This behavior persists for all d-values. However, the binding energy c field. For strong magnetic0 field strength, the donor donor impurity,behaviors we have as given inserted in Figs.the pressure3.10 a andand btemperature (d=0 a*). dependent material binding energies enhances significantly for any decreases as the impurity (d) increases. We Fig.can see 15a a significant and 15b decrease show thein the effect binding of pressure a* hydrostatic pressure and temperature values as and impurity position (d=0.5 ) on the (BE) * * = 3.044 we expected. Ω‘Ω energy as d increases from d=0.1 a to d=0.5as a . functionFor example, of at magnetic fieldand strength. The comparison between two d-valuesβ (d=0 and = 2 Ο0* π π π π * CONFLICT OF INTEREST the binding energy reduces significantly0.5 a*) show from that, 4.62499 as we R increase,to 2.55177 d, R the. binding β The authors declare that they have no c energy increases due to the great reduction in the ThisΟ resultπ π π π is due to the great reduction in the coulomb impurity energy (Eq. 4), as we competing interests. coulomb attraction energy (Eq. 4). In Fig.16, we mentioned earlier. The same qualitative behaviordisplay can the also results be observed of the in donorTable 4 binding with energy * REFERENCES for d=0.5 a . The behavior shown agrees with the [1] Bastard G., (1981), Hydrogenic impurity states in a quantum different quantitative behavior for = 5.412 . * (BE) behavior given in Fig.8 (for d=0 a with same well: A simple model. Phys. Rev. B. 24: 4714-4718. β Applications of silver Ω‘Ω¦ ,(reason). [2] Poonam V., Sanjiv K. M., (2019 0 Ο π π π π To see the effects of pressure and temperature parameters on the binding energy of the nanoparticles in diverse scctors. Int. J. Nano. Dimens.10: CONCLUSION 18-36. donor impurity, we have inserted the pressureIn conclusion,and temperature the exact dependent diagonalization material method [3] Porras-Montenegro N., Perez-Merchancano S., latge A., (1993), Binding energies and density of impurity states in had been used to solve the donor impurity spherical GaAsβ(Ga, Al)As quantum dots. J. Appl. Phys. 74: Hamiltonian in a heterostructure subjected to 7624-7628. ground-state [4] Ciftja O., (2013), Understanding electronic systems in an applied magnetic field. TheΩ‘Ω energy of GaAs/AlGaAs heterostructure had been semiconductor quantum dots, Phys. Scrip. 88: 058302- computed. Furthermore, the impurity effect on 058306. [5] Liang S., Xie W. F., (2011), The hydrostatic pressure and the ground-state energy had been shown. In temperature effects on a hydrogenic impurity in a spherical addition, the influence of the hydrostatic pressure, quantum dot. Eur. Phys. J. B. 81: 79-84. temperature and magnetic field on the binding [6] Holtz O., Qing Xiang Zh., (2004), Impurities confined in energy of the donor impurity can be summarized quantum structures, 1st ed, (Springer), 5-10. as follows: the donor impurity binding energy [7] Dingle R., Stormer H. L., Gossard A. C.,Wiegmann W., (1978), is a decreasing function of temperature for Electron mobilities in modulationβdoped semiconductor heterojunction superlattices.Appl. Phys. Lett. 33: 665-671. fixed values of pressure and magnetic field. For [8] Zhu J.-L., (1989), Exact solutions for hydrogenic donor states example the donor impurity binding energy in a spherically rectangular quantum well. Phys. Rev. B. 39: decrease from BE=8.3 R * to BE= 7.8 R * as we 8780-8786.
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390 Int. J. Nano Dimens., 10 (4): 375-390, Autumn 2019