三元混晶矩形量子阱线的表面和界面光学声子模  

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

作　　者：包锦[1] 闫祖威[1] BAO Jin;YAN Zu-wei(College of Science,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）》2020年第3期244-252,共9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)资助项目。

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,研究了含三元混晶的矩形量子阱线的表面和界面光学声子模。以GaAs/AlxGa1-xAs和ZnxCd1-xSe/ZnSe为例,获得了表面和界面光学声子模的色散关系以及表面和界面光学声子模的频率随混晶组分和量子阱线结构的变化关系。结果表明:与二元晶体量子阱线和三元混晶单量子线不同,在GaAs/AlxGa1-xAs和ZnxCd1-xSe/ZnSe量子阱线中分别存在十支和八支表面和界面光学声子模,这些表面和界面光学声子模的频率曲线分别位于二元晶体和三元混晶的体纵、横光学声子之间的频率区间内,且其能量随混晶组分和量子阱线结构的变化呈非线性变化,三元混晶的"单模"和"双模"性也在色散曲线中体现了出来。The surface and interface optical phonons in freestanding rectangular quantum well 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 and interface optical phonon frequencies as functions of the wave-vector,composition x,and the geometric structures of the quantum well wires in GaAs/AlxGa1-xAs and ZnxCd1-xSe/ZnSe quantum well wires systems are obtained and discussed.It is shown that different from quantum well wire systems of binary crystals and quantum wire systems of ternary mixed crystals,there are ten and eight branches of surface and interface optical phonon modes in the GaAs/AlxGa1-xAs and ZnxCd1-xSe/ZnSe quantum well wire systems of polar ternary mixed crystals.These modes localize in the frequency regions between the bulk longitudinal and transversal optical phonons of binary crystals and ternary mixed crystal,respectively.The surface and interface optical phonon modes non-linearly change in frequency with the composition and the geometric structures of rectangular quantum well 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：表面和界面光学声子模 三元混晶 矩形量子阱线 

分 类 号：O471.3[理学—半导体物理]