AAS Oscillation 16, 80, 87 AB Effect 15 AB Oscillation 15 AB Type

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Index AAS oscillation 16, 80, 87 atomic-force-microscopy 228 AB effect 15 Au 15 AB oscillation 15 AB type oscillation 76, 81, 86 backward scattering 56 acceleration equation 35 ballistic motion 4, 27 addition energy 67 ballistic regime 5 AFM 228, 243, 247 ballistic transport 1, 6, 28 Ag 3 band offset 190 Aharonov-Bohm effect 1, 15 BDD 220 Aharonov-Bohm flux 110 bend resistance 27 Aharonov-Bohm oscillation 16 Bethe ansatz 45 Aharonov-Bohm type oscillation bi-exciton 268 76 binary decision diagram 220 Al 43 blackbody emission 99 AlAs 105,176, 183, 199,228,249 blackbody radiation 101 AlAs/GaAs 22 Bloch condition 83 AIGaAs 104, 184, 228, 238, 247 Blochfrequency 199 AIGaAs/GaAs 99 Bloch oscillation 35, 102, 104, 199 AIGalnAs/lnP 179 Bloch's theorem 83, 140 AIGalnP 176 Bohr radius 4 AIGalnP /GaAs 177 Boltzmann constant 5,31 Altshuler-Aronov-Spivak oscilla­ Boltzmann distribution 64 tion 16, 72, 80 Boltzmann transport equation 3 analog computation 222 Boolean expression 220 Anderson localization 5, 8, 87, Boolean operation 220 109, 146 Born approximation 46, 56, 58 anisotropic etching 216 bosonization technique 25, 47 antidot disorder 80, 87 boundary roughness 54 antidot lattice 8, 72 Bragg reflection 1, 104, 187, 199 antidot potential 72 breakdown of quantum Hall effect aperture function 205 112 artificial atom 1, 66 Brillouin zone 35, 104 aspect ratio 73 bulk 4 274 Index bulk-current picture 109 Coulomb blockade oscillation 37, butterfly oscillation 77 66, 218 butterfly spectrum 8 Coulomb diamond 67 Biittiker-Landauer formula 85, Coulomb gap 66 111 Coulomb interaction 1, 4, 6, 50, 58, 67 CaF2 188 Coulomb oscillation 37, 66 cathodoluminescence 250, 257 coupled quantum well 195 cavity polariton 164 critical exponent of localization cavity quasimode 161 114 cavity resonance mode 161 critical randomness 9 center coordinate 111, 120 Cu 3 CEO 255 current probe 28 chaos 1,8 current source 32 chaotic orbit 72 current standard 33 charging effect 1 current-voltage characteristics 105 charging energy 4, 6, 31, 34, 37 cyclotron diameter 27 chemical potential 11, 51 cyclotron energy 61, 69 CL 250,257 cyclotron frequency 116 classical action 79 cyclotron motion 63 cleaved edge overgrowth 255 cyclotron orbit 72, 79, 90 Co 188 cyclotron radius 28, 55, 90, 132 coherence volume 149 cylinder-shaped microcavity 164 coherent destruction of tunneling cylindrical metal film 80 200 collimation 30 DBR 179,183 commensurability condition 90 DBRTD 207 commensurability oscillation 72 de Broglie wavelength 195 commensurability peak 72, 86 deep mesa etching 6 complex unitary matrix 9 defect mode 168 composite fermion 94 deformation potential 93 compressible and incompressible strips 132, 136 delocalized state 9 conductance fluctuation 1 density-density correlation function conductance quantization 1, 13, 46 22 density of states 9, 56, 64, 77, 84, constriction 36 133 Cooper pair 15, 18, 43 dephasing process 16 device trend 213 CoSi2 188 diagonal conductivity 75 CoSi2 /CaF2 188 Coulomb blockade 1,31,66, 187, diagonal resistivity 72 218 diamagnetic shift 239 Index 275 differential capacitance 133 electron-electron interaction 26, differential conductance 66 37, 66, 98 differential resistance 32 electron-electron scattering 5, 206 diffraction 187 electron heating 97 diffusion coefficient 4, 9, 18, 74, electron-hole pair 42 115 electron holography 15 diffusive motion 4 electron-phonon interaction 61 diffusive regime 5, 13, 80 electron-phonon scattering 5 disk-shaped micro cavity 164 electron temperature 99 disordered contact 126 electron wave 1 distributed Bragg reflector 179, electron wavefront 204 183 electron waveguide 196 distributed circuit 135 electroreflectance 104 DOS model 133 elliptic coordinates 25 double-barrier resonant tunneling energy-dispersive x-ray spec- diode 207 troscopy 232, 249 double-barrier structure 66 ensemble average 5 double slit 205, 210 envelope function 143 DRAM 213 environmental effect 31 drift velocity 91 equi-energy line 83 Drude conductivity 101 equilibration length 126 Drude formula 49 dynamical interaction 5 ergodic hypothesis 17 evanescent mode 82 EBL 210 exchange effect 70 EB lithography 216 exchange interaction 67, 70 edge channel 109 exciton 144 edge current 112, 120 extended state 9, 109 edge-current picture 109 edge magnetoplasmon 122 Fabry-Perot interferometer 191 edge state 45, 55, 132 Fabry-Perot micro cavity 161, 168 effective channel number 13 Fabry-Perot resonance 161 effective chemical potential 12 Fabry-Perot structure 183 effective mass 144, 195 Faraday configuration 97 effective-mass approximation 105, far-infrared 96 141,257 FEL 201 Einstein relation 9 Fermi energy 3, 5, 20, 22, 30, 38, electrochemical potential 66, 120 45, 54, 72, 121, 205, 206 electroluminescence 265 Fermi level 24, 37, 58, 66, 90, 109, electron affinity 67 111, 116, 133, 190 electron beam lithography 210 Fermi liquid 45 electron directional coupler 196 Fermi liquid theory 5,47 276 Index Fermi surface 47, 90 97, 114, 132, 152, 171, 198,201, Fermi velocity 3, 26 247, 255 Fermi wavelength 3, 6, 8, 13, 36, GalnAs 176 72,76 GalnAs/ AlInAs 61 Fermi wave number 3, 25, 54 GalnAs/GaAs 176, 199 Fermi wave vector 3, 90 GalnAs/InP 61, 207, 210 field-effect device 193 GalnAsP 176, 210 field-effect tunneling transistor GalnAsP/InP 171,174,179 188 GalnNAs/GaAs 179 filling fraction 170 gain profile 181 fine-area photoluminescence spec- galvanomagnetic effect 111 trum 229 GaN 176 fine structure constant 109 gas-source MBE 228, 265 FIR 96 Gauss's theorem 41 FIR spectroscopy 96 Ge 264 first Brillouin zone 140 geometrical resonance 90 FIR transmission spectroscopy 96 giant step 247 fluctuations of orbital susceptibility glancing-angle MBE 255 19 fluorescence 156 grating coupler 101 flux average 112 growth interruption 269 flux quantization 15, 18 guiding center 91 flux quantum 15, 80, 88, 109 guiding center coordinate 90 Fock-Darwin state 7, 68 Fourier transform 204 Hall conductivity 75 four-terminal geometry 111 Hall field 109 four-wave mixing 105, 198 Hall resistance 29 Frohlich interaction 63 Hall resistivity 72 free-electron laser 201 harmonic potential 6 Frenkel exciton 144 Hartree-Fock calculation 67 Fresnel-Fourier transform 187 Hartree-Fock theory 39 Friedel oscillation 58 Hartree potential 96 Friedel sum rule 39 hemispherical micro cavity 164 fusion technique 174 HEMT 224 heterostructure 4 GaAlAs 165, 176 high electron mobility transistor GaAlAs/AIAs 165,176 224 GaAs 22, 36, 50, 52, 66, 106, 150, higher harmonics 32 163,174,176,183,206,228, high-speed device 213 230, 238, 247 Hofstadter's butterfly 8, 77 GaAs/ AlAs 104, 228, 255 hot electron 101 GaAs/ AIGaAs 3, 61, 64, 72, 90, hot-electron diffraction device 210 Index 277 hot electron wave 205 Kosteritz-Thouless...lBerezinskii hot plasmon 101 transition 42 Hubbard model 45, 52 Kramers degeneracy 10 Hund's rule 67, 70 KTB transition 42 hysteresis 93 Kubo formula 12, 62 ideal lead 85 Landau diamagnetism 17, 20 ideal reservoir 11 Landauer's formula 1, 11, 22, 45, ideal wire 11 51, 111 Landau gauge 62, 90, 92 InAs 243 Landau level 61,90, 112, 120, 132 InAs/ AlGaSb 64 Landau subband 90 incoming channel 13 laser interference pattern 90 inelastic scattering 5, 16, 115 lateral superlattice 8, 90 inelastic scattering length 16 lattice vibration 5 inelastic scattering time 115 linear response theory 112 InGaAs 66, 164, 183, 228, 243 local current 27 InGaAs/GaAs 231 local current distribution 112 InGaAs quantum dot 183, 243 local electric field 27 InP 172, 176,228 localization in quantum Hall in-plane gate 6 regime 110 integer quantum Hall effect 9, localization length 8, 88, 117 109,120 localized state 109 interface roughness 106 LO phonon 61,206 interference 187 low-power device 213 interference device 206 LSI technology 187 interference effect 14, 31, 80 Luttinger-Kohn Hamiltonian 151 interference switch 205 Lyapunov exponent 79 inverse Bloch oscillation 201 inverse localization length 8, 110 macroscopic system 5 ion beam implantation 238 magic number 67 ion beam milling 238 magnetic depopulation 96 IQHE 120 magnetic-field modulation 93 magnetic flux 82 Josephson effect 34 magnetic focusing 27, 74 junction network 40 magnetic length 82, 112, 120, 132 magnetic moment 39 Kirchhoff's diffraction theory 205 magnetic unit cell 82 Kohn's theorem 7,98 magnetic Weiss oscillation 93 Kondo effect 39 magneto capacitance 132 Kondo temperature 39 magneto-fingerprint 15 Korringa relation 46 magnetophonon resonance 61 278 Index magnetoresistance 54, 64, 86, 90 negative differential conductance Maslov index 79 218 MBE 188,227,247,255 negative differential resistance mean free path 3,8, 13, 18,27, 190, 208 54, 80, 86, 90 negative magnetoresistance 9, 80 mesoscopic physics 31 neighboring confinement structure mesoscopic system 1 266 metal-insulator transition 8 Neumann-type computing architec- metallic dot 6 ture 220 metallic wire 6 Ni 93 metalorganic chemical vapor depo- nonlocal resistance 112, 126 sition 209, 227 nonlocal transport 27 metalorganic MBE 228 nonparabolicity 113 MgOjSi 176 normal order 147 Michaelson interferometer 96 nuclear relaxation time 46 micro cavity 1, 139, 157 microcavity laser 157 OMVPE 209, 227 micro-PL 240 optical atom 167 microsphere 164 optical pumping 184 microwave 32, 36 opto-electric effect 122 miniband collapse 200 orbital current 17, 20 MOBILE 223 orbital magnetism 17 MOCVD 209, 227 orbital susceptibility 19 MOCVD selective growth 238 organometallic vapor phase epitaxy model-solid theory 264 209, 227 modulation bandwidth 181 orthogonal 9 molecular beam epitaxy 227 outgoing channel 13 monostable-to-bistable
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  • Maximally Localized Wannier Functions: Theory and Applications

    Maximally Localized Wannier Functions: Theory and Applications

    REVIEWS OF MODERN PHYSICS, VOLUME 84, OCTOBER–DECEMBER 2012 Maximally localized Wannier functions: Theory and applications Nicola Marzari Theory and Simulation of Materials (THEOS), E´ cole Polytechnique Fe´de´rale de Lausanne, Station 12, 1015 Lausanne, Switzerland Arash A. Mostofi Departments of Materials and Physics, and the Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, London SW7 2AZ, United Kingdom Jonathan R. Yates Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United Kingdom Ivo Souza Centro de Fı´sica de Materiales (CSIC) and DIPC, Universidad del Paı´s Vasco, 20018 San Sebastia´n, Spain and Ikerbasque Foundation, 48011 Bilbao, Spain David Vanderbilt Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA (published 10 October 2012) The electronic ground state of a periodic system is usually described in terms of extended Bloch orbitals, but an alternative representation in terms of localized ‘‘Wannier functions’’ was introduced by Gregory Wannier in 1937. The connection between the Bloch and Wannier representations is realized by families of transformations in a continuous space of unitary matrices, carrying a large degree of arbitrariness. Since 1997, methods have been developed that allow one to iteratively transform the extended Bloch orbitals of a first-principles calculation into a unique set of maximally localized Wannier functions, accomplishing the solid-state equivalent of constructing localized molecular orbitals, or ‘‘Boys orbitals’’ as previously known from the chemistry literature. These developments are reviewed here, and a survey of the applications of these methods is presented. This latter includes a description of their use in analyzing the nature of chemical bonding, or as a local probe of phenomena related to electric polarization and orbital magnetization.