准二维强耦合激子有效质量的温度依赖性  

Temperature Dependence of Quasi-Two-Dimensional Strong-Coupling Excitons' Effective Mass

作　　者：额尔敦朝鲁[1] 于若蒙[2] 

机构地区：[1]河北科技师范学院凝聚态物理研究所,河北秦皇岛066004 [2]华中科技大学物理系,湖北武汉430074

出　　处：《光学学报》2009年第4期1105-1111,共7页Acta Optica Sinica

基　　金：河北省自然科学基金(A2008000463);河北科技师范学院博士基金(2006D001)资助

摘　　要：采用Tokuda改变的线性组合算符法和改进的Lee-Low—Pines变换法，研究了温度对量子阱中电子（空穴）与界面光学（IO）声子强耦合又与体纵光学（LO）声子弱耦合激子的有效质量的影响。结果表明，由电子（空穴）一体纵光学声子弱耦合所产生的激子有效质量（Mex^＊-LO）随量子阱宽N的增加而增大、随电子与李穴间相对距离ρ的增加而先增大后缓慢减小再趋于稳定，温度T对Mex^＊-LO及其随N和ρ变化的规律产生显著影响，同时，Mex^＊-LO随T的变化也强烈的受到量子尺寸效应的影响；由电子（空穴）-界面光学声子强耦合所产生的激子有效质量Mex^＊-LO.随N的增加而减小、随T的升高而增大、随ρ的增加而先增大后缓慢减小再趋于稳定，但T对Mex^＊-LO和ρ变化的规律无明显影响。The influences of the temperature on the effective mass of the exciton, for which the electron （hole） is strongly coupled with interface-optical phonons but weakly coupled with bulk-longitudinal-optical phonons in a quantum well, are studied by means of Tokuda＇s improved linear combination operator and a modified Lee-Low-Pines transformation method. The resuls indicate that the effective mass （Mex^＊-LO ） of the exciton, which is induced by the electron （hole） weakly coupled with bulk-longitudinal-optical phonons, will increase with the well width （N） increasing and first increase and then decrease, finally tends to a stable value with the distance between the electron and the hole （ρ） increasing. The influence of temperature onMex^＊-LO and its changing with N and ρ is obvious. The change of Mex^＊-LO with T is strongly related to the quantum-size effect. The effective mass Mex^＊-LO of tbe exciton, which is induced by the electron （hole） strongly coupled with interface-optical phonons, will decrease with increasing N, increase with increasing T and first increase and then decrease, finally tends to a stable value with increasing ρ. But the influence of temperature on Mex^＊-LO and its changing with N and ρ is not obvious.

关 键 词：凝聚体光学性质 激子 线性组合算符法 有效质量 温度依赖性 

分 类 号：O471.4[理学—半导体物理]