ISSN: 0256-307X 中国物理快报 Chinese Physics Letters

Volume 30 Number 7 July 2013 A Series Journal of the Chinese Physical Society Distributed by IOP Publishing Online: http://iopscience.iop.org/0256-307X http://cpl.iphy.ac.cn

C HINESE P HYSICAL S OCIET Y

Institute of Physics PUBLISHING CHIN. PHYS. LETT. Vol. 30, No. 7 (2013) 074702 An Immersed Boundary-Lattice Boltzmann Simulation of Particle Hydrodynamic Focusing in a Straight Microchannel *

SUN Dong-Ke(孙东科)**, JIANG Di(姜迪), XIANG Nan(项楠), CHEN Ke(陈科), NI Zhong-Hua(倪中华)** Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189

(Received 5 March 2013) An immersed boundary (IB)-lattice Boltzmamm method (LBM) coupled model is utilized to study the particle focusing in a straight microchannel. The LBM is used to solve the incompressible fluid flow over a regular Eulerian grid, while the IB method is employed to couple the bead-spring model which represents the fluid- particle interaction. After model validation, the simulations for hydrodynamic focusing of the single and multi particles are performed. The particles can be focused into the equilibrium positions under the pressure gradient and self-rotation induced forces, and the particle radius and Reynolds number are the key parameters influencing the focusing dynamics. This work demonstrates the potential usefulness of the IB-LBM model in studying the particle hydrodynamic focusing.

PACS: 47.27.nd, 47.11.−j, 87.85.gf, 04.60.Nc DOI: 10.1088/0256-307X/30/7/074702

The particle hydrodynamic focusing, which takes ticle dynamics at finite particle Reynolds number, all place when a fluid with suspended particles flows in of the work that we are aware of has been confined a microchannel at a sufficiently high Reynolds num- to considering the particle motions including tank- ber, has been developed as one of the most utilized treading, swinging, and tumbling,[19−21] and fluid- techniques in microfluidics.[1] During the focusing, the structure interactions.[22] A good understanding on uniformly distributed particles in the fluid tend to mi- particle hydrodynamic focusing is still lacking. There- grate to certain positions by the balance of forces as- fore, it is necessary to investigate the complex hydro- sociated with the fluid inertia and the influence of dynamical interactions by the IB-LBM coupled model. channel walls. Various simulations were successfully The aim of this work is to study the hydrodynamic carried out to study the focusing mechanism in mi- focusing of particles in a straight microchannel by the crochannels by the traditional Navier-Stokes equation- IB-LBM coupled model. We first present the simu- based methods,[2−5] however the fluid-particle interac- lation methodology involving the LB model for fluids tion is not fully considered in detail in all the studies. flow, the bead-spring model for particles, and the cou- The lattice Boltzmann method (LBM),[6] for its pling method by IBM. After discussing the numerical advantages in efficiency and parallel scalability, has results, a summary closes this letter. gained increasing popularity in the last two decades We adopt the standard lattice Bhatnagar–Gross– as an alternative numerical approach for solving prob- Krook (LBGK) approach with a single relaxation time lems in particle-fluid systems.[7−9] Ladd[10,11] has suc- scheme[6] to solve the LB equation. Accordingly, the cessfully applied the LBM to model particle-fluid sus- evolution equation with a force term can be expressed pensions, and the various numerical studies on parti- as[23] cle dynamics in suspensions were performed following 푓 (푥 + 푒 ∆푡, 푡 + ∆푡) − 푓 (푥, 푡) Ladd’s work.[12−15] However, a large number of grids 푖 푖 푖 for the particles should be employed when modeling 1 eq = − [푓푖(푥, 푡) − 푓푖 (푥, 푡)] + ∆푡퐹푖(푥, 푡), (1) accurately the physical boundaries of particles by the 휏 Ladd-type model, which limits the application of the where 푓푖(푥, 푡) is the particle distribution function model.[16] Recently, the immersed boundary method (PDF) representing the probability of finding a pseudo (IBM)[17] has emerged as a superior particle modeling fluid particle moving in the 푖th direction on the dis- [18] technique. Fogelson and Peskin have shown that crete lattice at position 푥 and time 푡, 푒푖 is the discrete this method is especially suitable for the simulation moving velocity of the pseudo fluid particle, ∆푡 is the of the fluid-particle system. Feng and Michaelides[16] time step, and 휏 is the relaxation time. The force first developed the IB-LBM coupled model and ap- term 퐹푖(푥, 푡) is considered to be caused by the pres- plied it to simulate the sedimentation of a large num- sure gradient and the interaction from the particles. ber of particles in an enclosure. Although much The D2Q9 topology,[6] in which the two-dimensional progress has been made towards elucidating the par- (2D) space is discretized into a regular square lattice

*Supported by the National Natural Science Foundation of China under Grant No 91023024, the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No 20110092110003, and the National Science Foundation for Post-doctoral Scientists of China under Grant No 2012M511647. **Corresponding author. Email: [email protected]; [email protected] © 2013 Chinese Physical Society and IOP Publishing Ltd 074702-1 CHIN. PHYS. LETT. Vol. 30, No. 7 (2013) 074702 including nine velocities, is employed in the present and the membrane configuration 푥푛 is updated ac- eq [19] work. The equilibrium distribution function 푓푖 is de- cording to the local flow velocity 푢푓 fined by ∑︁ 푢p = 푢(푥푛)훿(푥푓 − 푥푛), (10) 2 2 푓 eq [︁ 푒푖 · 푢 (푒푖 · 푢) 푢 ]︁ 푓푖 = 푤푖휌 1 + 3 2 + 4.5 4 − 1.5 2 , (2) 푐 푐 푐 where 훿(·) denotes a discretized Dirac delta function where 푢 is the macroscopic flow velocity. The discrete with a finite support domain. Since the 훿-function is velocities 푒푖 are given by not restricted a priori and can be chosen freely obey- ing the basic properties to maintain momentum and ⎧(0, 0), 푖 = 0, ⎪ angular momentum conservation,[17,20] we adopt the ⎨ (푖−1) (푖−1) [20] 푒푖 = (cos[ 2 휋], sin[ 2 휋])푐, 푖 = 1, 2, 3, 4, common decomposition for the 2D model, ⎪√ ⎩ 2(cos[ (2푖−9) 휋], sin[ (2푖−9) 휋])푐, 푖 = 5, 6, 7, 8, 4 4 훿(푟) = 휑(푥)휑(푦), (3) where 푐 = ∆푥/∆푡 is the lattice speed, and ∆푥 is the lattice spacing. In the D2Q9 scheme, the force term {︂1 − |푟|, |푟| ≤ 1, 휑(푟) = (11) 퐹푖(푥, 푡) in Eq. (1) can be expressed as 0, |푟| ≥ 1. (︁ 1 )︁ [︁ 푒 − 푢 푒 · 푢 ]︁ To validate the coupled IB-LBM model, the flow pass- 퐹 = 1 − 푤 3 푖 + 4.5 푖 푒 · 퐹 , 푖 2휏 푖 푐2 푐4 푖 ing over a circular cylinder, as shown in Fig. 1(a), is (4) taken as a benchmark to confirm that the model is working properly. The drag force coefficient 퐶 of the where 푤푖 are the weight coefficients given by 푤0 = 4/9, D cylinder can be accurately approximated by[25] 푤1,2,3,4 = 1/9 and 푤5,6,7,8 = 1/36, and 퐹 is the force on the fluid. The macroscopic fluid density 4휋 퐶D = , (12) 휌, velocity 푢 and kinematic viscosity 휈 can be ob- − 1 2 3 ∑︀ ∑︀ 1 ln 휑 2 − 0.738 + 휑 − 0.887휑 + 2.039휑 tained by 휌 = 푖 푓푖, 휌푢 = 푖 푐푖푓푖 + 2 퐹 ∆푡, and 1 1 2 2 2 휈 = 3 (휏 − 2 )푐 ∆푡, respectively. where the solid fraction is defined as 휑 ≡ 휋푅 /퐿 , 푅 The particle is represented by the bead-spring (BS) is the radius of the cylinder, and 퐿 is the side length [24] model including 푁 membrane Lagrange nodes, of the domain. In the simulation, we set 푅 = 5, 6, which are connected to their neighboring Lagrange 7, 8, 9, 퐿 = 40, and 휏 = 0.8. The difference between nodes by springs. The total energy 퐸 of the BS model the pressures at the inlet/outlet of the channel is set contains three parts, the elastic energy 퐸l stored in the 2 to be ∆푝 = 0.002휌푐푠. The LBM simulated data coin- stretch/compression spring, the bending energy 퐸b cides well with the analytical approximation solution stored in the bending springs, and the area energy 퐸a as shown in Fig. 1(b). representing the incompressibility. These three kinds of energies can be expressed as (a) Periodic boundary 4.0 in

ou t (b)

3.5 Simulated results 1 푁 (︁푙푛 − 푙0 )︁ ∑︁ Analytal approic ximation 퐸l = 퐾l , (5) 3.0 2 푛=1 푙0 D 푁 C 2.5 1 ∑︁ 2 (︁휃푛 − 휃푛,0 )︁ 퐸b = 퐾b tan , (6) 2 푛=1 2 2.0 2 1 (︁푠 − 푠0 )︁ 1.5

퐸a = 퐾a , (7) p Pressure boundary, 2 푠0 Periodic boundary p Pressure boundary, 5.0 6.0 7.0 8.0 9.0 R where 푙 is the length of the 푛th spring element, 휃 de- 푛 푛 Fig. 1. notes the angle of the bending element, 푠 is the surface (a) Boundary conditions and (b) drag coefficient 퐶D as a function of the cylinder radius 푅 for the flow area of the membrane, and 푁 is the total number of passing over a circular cylinder. spring elements; 푙 , 휃 and 푠 denote the references of 0 푛,0 0 Next, the simulation of the hydrodynamic focus- length, bending angle, and surface area, respectively. ing of the single particle is carried out. The compu- In this work, the magnitude of 퐾 is set to be 25, and a tational domain is a rectangular channel of 퐿 × 퐻 = 퐾 : 퐾 : 퐾 = 1 : 1 : 1000 is kept. The spring force l b a 160 µm × 80 µm. Initially, a circular particle of radius on each Lagrange node 푛 is calculated by 푅 is released into the fluid near the inlet, and the fluid stream into the channel from the left side under 푓(푥푛) = −휕퐸/휕푥푛 with 퐸 = 퐸l + 퐸b + 퐸a. (8) the acceleration 푎 = (푎푥, 푎푦), as shown in Fig. 2. The The fluid-particle interaction is coupled according to periodic boundary conditions are imposed on the left [17] the principle of IBM. The forces 푓(푥푛) are dis- and right sides, and the top and bottom sides are set tributed to the adjacent fluid nodes 푥푓 by to be solid walls. The channel Reynolds number is ∑︁ defined as 푅푒푐 := 푢0퐻/휈, where 푢0 is the theoreti- 퐹푓 = 푓(푥푛)훿(푥푛 − 푥푓 ), (9) p cal characteristic velocity of the fluid flow, and it is 074702-2 CHIN. PHYS. LETT. Vol. 30, No. 7 (2013) 074702

2 computed according to 푢0 = 푎푥퐻 /8휈. In the simula- of the vertical position of the single particle with vari- tion, other parameters were chosen as 휌 = 1000 kg/m3, ous initial positions. Despite different initial positions, −6 2 3 2 휈 = 1.0 × 10 m /s, 푎푥 = 1.0 × 10 m/s , 푎푦 = 0, the particles in all the cases experience a short stage of ∆푥 = 1.0 × 10−6 m, ∆푡 = 1.0 × 10−7 s and 푁 = 32. lateral migration, then reach their steady state, and fi- nally keep moving on the same position. It can be con-

a cluded that the particles with different initial positions can be focused onto the same equilibrium position at the same 푅푒푐, and the final equilibrium position ofa

H particle is independent of the initial position.

(x֒y) y ↼x0,y0) 0.03 Net lift force, Fn x o 0.02 Rotation-induced, Fω L Pressure-induced, Fp

N) 0.01 Fig. 2. Schematic of the hydrodynamic focusing of the -3 particles in a straight microchannel. 0.00 F (10 80 -0.01

-0.02 60 0.0 1.0 2.0 3.0 4.0 5.0 6.0 t ↼-3 s↽ F 40 p y ( m m) wp Fig. 4. Time history of lift forces on the particle of 푅 = 7.2 µm at 푅푒푐 = 64. 20 t1 t2 t@

t0 Fω 3.5 0 0 30 60 90 120 150 3.0 x (mm)

m) 2.5

Fig. 3. Migration of the particle with 푅 = 7.2 µm at -5 y0=1.0 y =1.5 푅푒푐 = 64 (푡0 = 0, 푡1 = 3.6 ms, 푡2 = 9.0 ms). 2.0 0 (10

p y0=2.0 y y =2.5 Figure 3 shows the simulated single particle evolu- 1.5 0 y0=3.0 tion with the developed nonuniform flow field. Under y0=3.5 1.0 the drag and shear of the fluid, the particle is mov- 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 ing along the flow direction with a self-rotation veloc- 0t (1 -3 s) ity 휔p, as shown in Fig. 3. Because the self-rotation Fig. 5. Time history of vertical position for the particle will induce a lift force on the particle,[26] the parti- of 푅 = 7.2 µm with various initial positions at 푅푒푐 = 64. cle considered here suffers from the rotation-induced ∑︀ force 퐹휔, which is computed by 퐹휔 = − 푛 푓(푥푛) · 푗. As the character of the flow field is determined by Meanwhile, the particle suffers from the pressure- Reynolds number, the simulations of a single particle induced lift force 퐹p due to the nonuniform veloc- focusing at different Reynolds numbers are performed. ity field. In the present simulation, the pressure- Five particles of 푅1−5 = {5.0, 6.0, 7.0, 8.0, 9.0} µm are induced force on the particle is computed by 퐹p = considered and the corresponding number of Lagrange ∑︀ 푛[휎 · 푛 − 휌푢(푢 · 푛)]퐴푛 · 푗, where 휎 is the stress ten- nodes are 푁1−5 = 22, 27, 31, 36, 40. Table 1 lists the sor and 푛 is the outward normal vector of node 푛 on comparison of vertical equilibrium positions for parti- the particle, 퐴푛 is the area supporting node 푛, and 푗 cles with different radius 푅 at 푅푒푐 = 45, 64, 90, 128. is the unit vector along the 푦-axis. The net lift force It indicates that the equilibrium position moves to- can be obtained from 퐹푛 = 퐹휔 + 퐹p, subsequently. wards the channel centerline with the increase of 푅푒푐 Figure 4 presents the time history of the forces on despite different 푅. This can be attributed to the the particle. At the initial stage, the pressure- and competition between the forces induced by the pres- the rotation-induced forces are in opposite directions, sure gradient and the particle self-rotation. At a lower i.e., 퐹푛 = 퐹휔 + 퐹p > 0, which imparts an accelera- 푅푒푐, a small pressure-induced force is exerted on the tion to the particle. The particle starts moving from particle, and the forces should be balanced near the the place near the wall to the channel center. After channel wall. When 푅푒푐 is increased, the pressure- that, the fluid-particle system enters the developing induced force will be enhanced more rapidly than the stage. At the developing stage, the rotation-induced self-rotation induced force. The particle has to mi- force goes up and then down, and the pressure-induced grate further inward across the streamlines to make force becomes trending down and then up. Finally, the forces balanced. Moreover, the particles of differ- the increase and decrease of two forces terminate, and ent radius tend to migrate into different equilibrium the particle reaches its equilibrium position when the positions under the same 푅푒푐. The larger the particle forces are balanced. Figure 5 displays the time history radius, the more inward is the equilibrium position. 074702-3 CHIN. PHYS. LETT. Vol. 30, No. 7 (2013) 074702

Table 1. Comparison of the equilibrium positions for particles simulated the focusing of single and multi particles with different radius 푅(µm) and Reynolds numbers 푅푒푐. in a straight channel. The results suggest that the 푒 Reynolds number and particle radius are the key pa- Vertical equilibrium position 푦p(µm) 푅푒푐 푅=5.0 푅=6.0 푅=7.0 푅=8.0 푅=9.0 rameters influencing the focusing dynamics. This 45 23.969 24.419 24.943 25.492 26.099 work demonstrates that the present model can be used 64 24.275 24.851 25.279 25.855 26.403 to provide physical insights into the underlying mecha- 90 25.256 25.723 26.175 26.648 27.275 nism of hydrodynamic focusing. Extending the model 128 27.137 27.535 27.981 28.557 29.163 to three-dimensional situations is necessary for more Finally, the simulations for the hydrodynamic fo- realistic simulations in further work. cusing of multi particles are performed in a straight The authors thank Dr. Tian Fang-Bao at Vander- channel of 퐿 × 퐻 = 240 µm×80 µm. Initially, six par- bilt University for helpful comments and discussions. ticles are released at the place nearby the channel in- let. Other conditions and numerical parameters are set the same as those in the case of Fig. 2. Figure 6 References indicates the simulated evolution of the focusing pat- tern for the fluid particle system. It can be seen that [1] Amini H, Sollierand E, Weaver W M and DiCarlo D 2012 the six randomly placed particles are firstly separated Proc. Natl. Acad. Sci. U.S.A. 109 11593 from a dense cluster into a loose pattern in a very [2] Ookawara S, Street D and Ogawa K 2006 Chem. Eng. Sci. 61 3714 short time, and finally ordered in regular trains in [3] D’Avino G, Romeo G, Villone M M, Greco F, Netti P A parallel along the streamlines with the development and Maffettone P L 2012 Lab Chip 12 1638 of flow field. These ordered particles maintain uni- [4] Prohm C, Gierlak M and Stark H 2012 Eur. Phys. J. E 35 form longitudinal spacing due to particle-particle in- 80 [5] Yang W and Zhou K 2012 Chin. Phys. Lett. 29 064702 teraction within and across the streamlines, in agree- [6] Qian Y H, d’Humières D and Lallemand P 1992 Europhys. ment with previous experimental observations in the Lett. 17 479 references.[27] [7] Lallemand P, Luo L S and Peng Y 2007 J. Comput. Phys. 226 1367 80 [8] Sun D K, Zhu M F, Pan S Y and Raabe D 2011 Comput. (a) Math. Appl. 61 3585 60 [9] Feng Y T, Han K and Owen D R J 2010 Int. J. Numer. Methods Eng. 81 229 40 [10] Ladd A J C 1994 J. Fluid Mech. 271 285 y ( m m) 20 Flow direction [11] Ladd A J C 1994 J. Fluid Mech. 271 311 [12] Chun B and Ladd A J C 2006 Phys. Fluids 18 031704 0 [13] Ku X K and Lin J Z 2009 Phys. Scr. 80 025801 80 (b) [14] Kilimnik A, Mao W and Alexeev A 2011 Phys. Fluids 23 60 123302 [15] Sun D K, Xiang N, Chen K and Ni Z H 2013 Acta Phys. 40 Sin. 62 024703 (in Chinese) y ( m m) [16] Feng Z G and Michaelides E E 2004 J. Comput. Phys. 195 20 602 0 [17] Peskin C S 2002 Acta Numer. 11 479 (c) [18] Fogelson A L and Peskin C S 1988 J. Comput. Phys. 79 50 [19] Zhang J F, Johnson P C and Popel A S 2007 Phys. Biol. 4 60 285 40 [20] Krüger T, Varnik F and Raabe D 2011 Comput. Math. Appl. 61 3485 y ( m m) 20 [21] Shen Z and He Y 2012 Chin. Phys. Lett. 29 024703 [22] Xia Y, Lu D T, Liu Y and Xu Y S 2009 Chin. Phys. Lett. 0 0 30 60 90 120 150 180 210 240 26 034702 x (mm) [23] Guo Z L, Zheng C G and Shi B C 2002 Phys. Rev. E 65 046308 Fig. 6. Evolution for the six particles of 푅 = 7.2 µm [24] Tsubota K I and Wada S 2010 Phys. Rev. E 81 011910 and the Poiseuille flow field at 푅푒푐 = 64: (a) 푡 = 0, (b) [25] Sangani A S and Acrivos A 1982 Int. J. Multiphase Flow 8 푡 = 0.6 ms, (c) 푡 = 18.0 ms. 193 In summary, an IB-LBM coupled model has been [26] Chen M, Yao Q, Luo L S 2006 Int. J. Comput. Fluid Dyn. 20 391 utilized to investigate the particle hydrodynamic fo- [27] Russom A, Gupta A K, Nagrath S, DiCarlo D, Edd J F and cusing. After validating the coupled model, we have Toner M 2009 New J. Phys. 11 075025

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076101 A Band-Gap Energy Model of the Quaternary Alloy InxGayAl1−x−yN using Modified Simplified Coherent Potential Approximation ZHAO Chuan-Zhen,ZHANG Rong, LIU Bin, LI Ming, XIU Xiang-Qian, XIE Zi-Li, ZHENG You-Dou 076102 Low-Dose 1 MeV Electron Irradiation-Induced Enhancement in the Photoluminescence Emission of Ga-Rich InGaN Multiple Quantum Wells ZHANG Xiao-Fu, LI Yu-Dong, GUO Qi, LU Wu 076201 The Anomalous Temperature Effect on the Ductility of Nanocrystalline Cu Films Adhered to Flexible Substrates HU Kun, CAO Zhen-Hua, WANG Lei, SHE Qian-Wei, MENG Xiang-Kang 076202 The Material Behavior and Fracture Mechanism of a Frangible Bullet Composite LI Jian, RONG Ji-Li, ZHANG Yu-Ning, XU Tian-Fu, LI Bin 076401 Harnessing Light and Single Masks to Create Multiple Patterns in a Ternary Blend with Photoinduced Reaction PAN Jun-Xing, ZHANG Jin-Jun, WANG Bao-Feng, WU Hai-Shun, SUN Min-Na 076402 Partial Order in Potts Models on the Generalized Decorated Square Lattice -Pu, CHEN Jing, CHEN Qiao-Ni, XIE Zhi-Yuan, KONG Xin, ZHAO Hui-Hai, Bruce Normand, XIANG Tao

CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES 077101 The Structural, Electronic and Elastic Properties, and the Raman Spectra of Orthorhombic CaSnO3 through First Principles Calculations A. Yangthaisong

077102 A Density Functional Study of the Gold Cages MAu16 (M = Si, Ge, and Sn) TANG Chun-Mei, ZHU Wei-Hua, ZHANG Ai-Mei, ZHANG Kai-Xiao, LIU Ming-Yi 077201 Enhanced Performance and Stability in Polymer Photovoltaic Cells Using Ultraviolet-Treated PEDOT:PSS XU Xue-Jian, YANG Li-Ying, TIAN Hui, QIN Wen-Jing, YIN Shou-Gen, ZHANG Fengling 077301 The Effect of Intraband Transitions on the Optical Spectra of Metallic Carbon Nanotubes T. Movlarooy 077302 The Nuclear Dark State under Dynamical Nuclear Polarization YU Hong-Yi, LUO Yu, YAO Wang 077303 Room-Temperature Multi-Peak NDR in nc-Si Quantum-Dot Stacking MOS Structures for Multiple Value Memory and Logic QIAN Xin-Ye, CHEN Kun-Ji, HUANG Jian, WANG Yue-Fei, FANG Zhong-Hui, XU Jun, -Fan 077304 Quantum Size and Doping Concentration Effects on the Current-Voltage Characteristics in GaN Resonant Tunneling Diodes Hassen Dakhlaoui 077305 The Unconventional Transport Properties of Dirac Fermions in Graphyne LIN Xin, WANG Hai-Long, PAN Hui, XU Huai-Zhe 60 077306 The C–V and G/ω–V Electrical Characteristics of Co γ-Ray Irradiated Al/Si3N4/p-Si (MIS) Structures S. Zeyrek, A. Turan, M. M. B¨ulb¨ul 077307 The Effect of Multiple Interface States and nc-Si Dots in a Nc-Si Floating Gate MOS Structure Measured by their G–V Characteristics , MA Zhong-Yuan, CHEN Kun-Ji, JIANG Xiao-Fan, LI Wei, HUANG Xin-Fan, XU Ling, XU Jun, FENG Duan 077308 Fano-Resonance of a Planar Metamaterial HUANG Wan-Xia 077402 An Insight into the Structural, Electronic and Transport Characteristics of XIn2S4 (X = Zn, Hg) Thiospinels using a Highly Accurate All-Electron FP-LAPW+Lo Method Masood Yousaf, M. A. Saeed, Ahmad Radzi Mat Isa, H. A. Rahnamaye Aliabad, M. R. Sahar

077403 The Optical Study of Single Crystalline Cs0.8(Fe1.05Se)2 with High N´eelTemperature YUAN Rui-Hua, DONG Tao, WANG Nan-Lin 077404 The Finite Temperature Effect on Josephson Junction between an s-Wave Superconductor and an s±-Wave Superconductor WANG Da, LU Hong-Yan, WANG Qiang-Hua 077501 Synthesis and Characterization of Alkaline-Earth Metal (Ca, Sr, and Ba) Doped Nanodimensional LaMnO3 Rare-Earth Manganites Asma Khalid, Saadat Anwar Siddiqi, Affia Aslam 077502 A First-Principles Investigation of the Carrier Doping Effect on the Magnetic Properties of Defective Graphene LEI Shu-Lai, LI Bin, HUANG Jing, LI Qun-Xiang, YANG Jin-Long 0 077503 Room-Temperature d Ferromagnetism in Nitrogen-Doped In2O3 Films SUN Shao-Hua, WU Ping, XING Peng-Fei 077701 Wafer-Scale Flexible Surface Acoustic Wave Devices Based on an AlN/Si Structure ZHANG Cang-Hai, YANG Yi, ZHOU Chang-Jian, SHU Yi, TIAN He, WANG Zhe, XUE Qing-Tang, REN Tian-Ling 077801 Magnetic-Field-Induced Stress-Birefringence in Laminate Composites of Terfenol-D and Polycarbonate LUO Xiao-Bin, WU Dong, ZHANG Ning 077802 The Fano-Like Resonance in Self-Assembled Trimer Clusters ZHANG Mei, LI Liang-Sheng, ZHENG Ning, SHI Qing-Fan

CROSS-DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY 078101 Overcoming Decomposition with Order-Reversed Quenching Obtained by Flash Melting SI Ping-Zhan, XIAO Xiao-Fei, FENG He, YU Sen-Jiang, GE Hong-Liang 078501 A Low Specific on-Resistance SOI Trench MOSFET with a Non-Depleted Embedded p-Island FAN Jie, ZHANG Bo, LUO Xiao-Rong, LI Zhao-Ji 078502 High-Efficiency InGaN/GaN Nanorod Arrays by Temperature Dependent Photoluminescence WANG Wen-Jie, CHEN Peng, YU Zhi-Guo, LIU Bin, XIE Zi-Li, XIU Xiang-Qian, WU Zhen-Long, XU Feng, XU Zhou, HUA Xue-Mei, ZHAO Hong, HAN Ping, SHI Yi, ZHANG Rong, ZHENG You-Dou

078503 A Distributed Phase Shifter Using Bi1.5Zn1.0Nb1.5O7/Ba0.5Sr0.5TiO3 Thin Films LI Ru-Guan, JIANG Shu-Wen, GAO Li-Bin, LI Yan-Rong 078801 Optimization of Metal Coverage on the Emitter in n-Type Interdigitated Back Contact Solar Cells Using a PC2D Simulation ZHANG Wei, CHEN Chen, JIA Rui, Janssen G. J. M., ZHANG Dai-Sheng, XING Zhao, Bronsveld P. C. P., Weeber A. W., JIN Zhi, LIU Xin-Yu

COMMENTS AND REPLIES 079901 Comment on “Improvement of Controlled Bidirectional Quantum Direct Communication Using a GHZ State” [Chin. Phys. Lett. 30 (2013) 040305] LIU Zhi-Hao, CHEN Han-Wu 079902 Reply to the Comment on “Improvement of Controlled Bidirectional Quantum Direct Communication Using a GHZ State” [Chin. Phys. Lett. 30 (2013) 040305] YE Tian-Yu, JIANG Li-Zhen 079903 Comment on “Cryptanalysis and Improvement of a Quantum Network System of QSS-QDC Using χ-Type Entangled States” [Chin. Phys. Lett. 29 (2012) 110305] LIU Zhi-Hao, CHEN Han-Wu 079904 Reply to the Comment on “Cryptanalysis and Improvement of a Quantum Network System of QSS-QDC Using χ-Type Entangled States” [Chin. Phys. Lett. 29 (2012) 110305] GAO Gan, FANG Ming, CHENG Mu-Tian