|本期目录/Table of Contents|

多层球形核壳量子点中光学振动模的三元混晶效应(PDF)

《内蒙古大学学报(自然科学版)》[ISSN:1000-9035/CN:22-1262/O4]

期数:
2019年06期
页码:
610-618
栏目:
研究论文
出版日期:
2019-11-15

文章信息/Info

Title:
Ternary Mixed Crystal Effect of Optical Vibration Modes in Multilayer Spherical Core-Shell Quantum Dots
作者:
刘 叶谢 慧邢 雁
内蒙古大学物理科学与技术学院,呼和浩特 010021
Author(s):
LIU YeXIE HuiXING Yan
School of Physical Science and Technology,Inner Mongolia University,Hohhot 010021,China
关键词:
光学声子模 核壳量子点 三元混晶
Keywords:
optical phonon mode core-shell quantum dot ternary mixed crystal
分类号:
-
DOI:
-
文献标识码:
A
摘要:
考虑三元混晶的“单模”与“双模”性,利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多层球形核壳量子点中的光学声子模.选取InN/InxGa1-xN/InN和ZnSe/ZnSxSe1-x/ZnSe两种核壳结构进行了数值计算,其中InxGa1-xN为单模型三元混晶,ZnSxSe1-x为双模型三元混晶,给出了两种结构中声子模频率随混晶组分、量子点尺寸以及角量子数的变化关系.结果表明,InN/InxGa1-xN/InN和ZnSe/ZnSxSe1-x/ZnSe结构中分别存在着5支和7支界面/表面光学声子模,且均具有特殊的混晶效应,具体表现在各支声子模的频率对组分x有不同的依赖关系.当组分x>0.8时,在ZnSe/ZnSxSe1-x/ZnSe结构中,模6、7重合为一支.同时发现各支声子模的频率对内壳层厚度γ1和较小的量子数l的依赖性较强.
Abstract:
Considering the one-mode and two-mode behaviors of ternary mixed crystals (TMCs),the optical phonon modes in multilayer spherical core-shell quantum dots containing of TMCs are discussed based on the dielectric continuum approach and modified random-element-isodisplacement model.Numerical calculations on the InN/InxGa1-xN/InN (“one-mode” TMC) and ZnSe/ZnSxSe1-x/ZnSe (“two-mode” TMC) core-shell structures have been performed.A detailed discussion of optical phonon mode frequencies as functions of components x and quantum dot size and quantum number l are given.The results show that there are five and seven branches of interface/surface optical phonon modes in InN/InxGa1-xN/InN and ZnSe/ZnSxSe1-x/ZnS structures,respectively.The mixed crystal effect has different influence on optical phonon mode frequencies.When x>0.8,modes 6 and 7 overlap into one mode in the ZnSe/ZnSxSe1-x/ZnSe structure.It is also found that the phonon frequencies are strongly dependent on the inner shell thickness γ1 and smaller quantum number l.

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备注/Memo

备注/Memo:
收稿日期:2019-05-09; 修回日期:2019-06-21
基金项目:内蒙古自治区高等学校科学研究项目资助(NJZZ19001)
作者简介:刘 叶(1993-),女,内蒙古赤峰人,2016级硕士研究生.
通信作者:邢 雁(1973-),女,内蒙古乌兰察布人,副教授,博士.E-mail:xingy@imu.edu.cn
更新日期/Last Update: