Asymmetry Localized Modes in an Anharmonic Sphalerite-Structure Lattice  

作　　者：ZHOU Guang-Hui XIA Qing-Lin PAN Liu-Xian YAN Jia-Ren 周光辉;夏庆林;潘溜仙;颜家壬(Department of Physics and Institute of Nonlinear Science,Hunan Normal University,Changsha 410081;Department of Physics,Yiyang Teachers College,Yiyang 413049;International Center for Materials Physics,Chinese Academy of Sciences,Shenyang 110015)

机构地区：[1]Department of Physics and Institute of Nonlinear Science,Hunan Normal University,Changsha 410081 [2]Department of Physics,Yiyang Teachers College,Yiyang 413049 [3]International Center for Materials Physics,Chinese Academy of Sciences,Shenyang 110015

出　　处：《Chinese Physics Letters》2000年第12期899-901,共3页中国物理快报（英文版）

基　　金：Supported by the National Nature Science Foundation of China under Grant No.19975013;by the Science Foundation of Hunan Education Commission under Grant No.301566.

摘　　要：We numerically study the intrinsic localized vibrational modes in a diatomic chain with different masses and alternating force constants between nearest neighbors.This model simulates a row of atoms in the<111>direction of sphalerite-structure crystal.We found that the harmonic and quartic anharmonic terms in the nearest-neighbor interaction potential produce the intrinsic localized modes with frequencies above the optical branch or in the gap of the linear spectrum,the distribution patterns of atom amplitudes are asymmetry with a form of quasi-even-or quasi-odd-parity,and the inclusion of cubic term in the potential lowers the frequencies of the modes and introduces static displacements for the atoms.

关 键 词：HARMONIC QUASI NEIGHBOR 

分 类 号：O56[理学—原子与分子物理]