三元混晶核壳量子点中的光学声子模  

Optical Phonon Modes in Core-shell Quantum Dots Consisting of Ternary Mixed Crystals

作　　者：刘丽萍[1] 邢雁[1] 

机构地区：[1]内蒙古大学物理科学与技术学院,呼和浩特010021

出　　处：《内蒙古大学学报（自然科学版）》2016年第5期500-507,共8页Journal of Inner Mongolia University：Natural Science Edition

基　　金：内蒙古自治区高等学校科学研究项目(NJZY14009);内蒙古大学高层次人才引进科研启动项目(No.135146)资助

摘　　要：采用介电连续模型和改进的无规元素等位移模型研究了含三元混晶的球形核壳量子点中的光学声子模,选取GaAs/Al_xGa_(1-x)As和ZnS/Zn1-xCdxS两种球形异质结构进行了数值计算.结果表明,含双模型三元混晶的GaAs/Al_xGa_(1-x)As量子点中存在五支界面/表面光学声子模,含单模型三元混晶的ZnS/Zn1-xCdxS量子点中存在三支界面/表面光学声子模,且两种结构中的界面/表面光学声子模频率随组分x呈现明显的非线性变化,当量子数l较小(l≤7)时,声子模的频率对混晶组分x和壳层厚度的依赖性较大.Using a dielectric continuum model approach and a modified random-element-isodis- placement model,the optical Phonon modes are studied for spherical core-shell quantum dots consisting of ternary mixed crystals. The numerical calculations for GaAs/AlxGa1-x As and ZnS/Zn1-x CdxS systems are performed. The results reveal that there are five branches interface/surface optical phonon modes in GaAs/AlxGa1-xAs system,and there are three branches optical phonon modes in ZnS/Zn1-xCdxS system. The effects of the one-mode and two-mode behaviors are considered. It is also found that ternary mixed effects have more important influences on the optical phonon frequen- cies for the small quantum number l.

关 键 词：光学声子模 三元混晶 核壳量子点 

分 类 号：O471.3[理学—半导体物理]