晶格热振动对准二维强耦合极化子有效质量的影响  

Effects of lattice vibration on the effective mass ofquasi-two-dimensional strong-coupling polaron

作　　者：额尔敦朝鲁[1] 李树深[2] 肖景林[3] 

机构地区：[1]河北科技师范学院数理系,秦皇岛066004 [2]中国科学院半导体研究所,半导体超晶格国家重点实验室,北京100083 [3]内蒙古民族大学物理与机电学院,通辽028043

出　　处：《物理学报》2005年第9期4285-4293,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10174076);国家重点基础研究专项经费(批准号:G2001CB309500);内蒙古自然科学基金(批准号:200208020110);内蒙古高校重大科研项目基金(批准号:NJ02074)资助的课题.~~

摘　　要：采用Tokuda改变的线性组合算符法和改进的LLP变分法,研究了晶格热振动对无限势垒量子阱中电子与界面光学声子强耦合、与体纵光学声子弱耦合系统的影响,推导出作为阱宽和温度函数的极化子有效质量的表达式.尤其得到了量子阱中极化子的振动频率及其随阱宽和温度变化的规律.对KIAgClKI量子阱进行了数值计算,结果表明,极化子的振动频率和有效质量随阱宽的增加而减小、随温度的升高而减小,但不同支声子与电子相互作用对极化子的振动频率和有效质量的贡献以及它们随阱宽和温度的变化情况大不相同.The effects of lattice vibration on the system in which the electron is weakly coupled with bulk longitudinal optical phonons and strongly coupled with interface optical phonons in an infinite quantum well were studied by using Tokuda＇ linear-combination operator and a modified LLP variational method. The expressions for the effective mass of the polaron in a quantum well QW as functions of the well＇s width and temperature were derived. In particular, the law of the change of the vibration frequency of the polaron changing with well＇ s width and temperature are obtained. Numerical results of the effective mass and the vibration frequency of the polaron for Kl/AgCl/Kl QW show that the vibration frequency and the effective mass of the polaron decrease with increasing well＇s width and temperature, but the contribution of the interaction between the electron and the different branches of phonons to the effective mass and the vibration frequency and the change of their variation with the well＇ s width and temperature are greatly different.

关 键 词：量子阱 强耦合极化子 振动频率 有效质量 温度依赖性 晶格热振动 有效质量 界面光学声子 电子相互作用 线性组合算符法 二维 温度变化 

分 类 号：O734[理学—晶体学]