三元混晶矩形量子线的表面光学声子模  

Surface Optical Phonon Modes in Rectangular Quantum Wires of Polar Ternary Mixed Crystals

作　　者：包锦[1] 闫祖威[1] BAO Jin;YAN Zu-wei(College of Sciences,Inner Mongolia Agricultural University,Hohhot 010018,China)

机构地区：[1]内蒙古农业大学理学院,呼和浩特010018

出　　处：《内蒙古大学学报（自然科学版）》2018年第6期597-604,共8页Journal of Inner Mongolia University：Natural Science Edition

基　　金：国家自然科学基金(11664030;11364028);内蒙古农业大学博士科研基金(BJ-0833)项目资助

摘　　要：运用改进的无规元素等位移模型和玻恩-黄近似,结合介电连续模型,研究了三元混晶矩形量子线系统的表面光学声子模.以AlxGa1-xAs和ZnxCd1-xSe为例,获得了表面光学声子模的色散关系以及表面光学声子模的频率随混晶组分和量子线结构的变化关系.结果表明:与二元晶体量子线不同,在三元混晶量子线系统中存在四支表面光学声子模,这四支表面光学声子模的频率曲线位于三元混晶的体纵、横光学声子的频率区间内,且其能量随混晶组分和量子线结构的变化而呈非线性变化.三元混晶的"单模"和"双模"性也在色散曲线中体现出来.Surface optical phonons in freestanding rectangular quantum wire systems of polar ternary mixed crystals are investigated with the modified random-element-isodisplacement model and the Born-Huang approximation based on the dielectric continuum model. The numerical results of the surface optical phonon frequencies as functions of the wave-vector,composition x, and geometric structures of the quantum wires in A1.GalxAs and Zn.CdlxSe quantum wire systems are obtained and discussed. It is shown that different from quantum wire systems of binary crystals, there are four branches of surface optical phonon modes in quantum wire systems of polar ternary mixed crystals to localize in the frequency regions between the bulk longitudinal and transversal optical phonons in ternary mixed crystal,and the surface optical phonon modes non-linearly change in frequency with the composition and the geometric structures of rectangular quantum wire systems of polar ternary mixed crystals. The effects of ＂one mode＂ and ＂two mode＂ behaviors of the ternary mixed crystals are shown in the dispersion curves.

关 键 词：表面光学声子模 三元混晶 矩形量子线 

分 类 号：O471.3[理学—半导体物理]