Influence of temperature and LO phonon on the effective mass of bipolarons in polar semiconductor quantum dots

作     者：辛伟 高忠明 韩超 额尔敦朝鲁 

作者机构：Institute of Condensed Matter PhysicsHebei Normal University of Science&Technology 

出 版 物：《Optoelectronics Letters》 (光电子快报（英文版）)

年 卷 期：2012年第8卷第6期

页      面：477-480页

核心收录：

学科分类：080903[工学-微电子学与固体电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 070205[理学-凝聚态物理] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0702[理学-物理学] 

基　　金：supported by the Science and Technology Development Plan of Qinhuangdao(No.201101A027) 

主　　题：Electron correlations Electron phonon interactions Semiconductor quantum dots 

摘      要：The temperature and LO phonon effects of the bipolaron in polar semiconductor quantum dots （QDs） are studied by using the Tokuda modified linear-combination operator method and the Lee-Low-Pines variational method. The expressions for the mean number ofLO phonons and the effective mass of the bipolaron are derived. Numerical results show that the mean number of LO phonons of the bipolaron decreases with increasing the temperature and the relative distance r between two electrons, but increases with increasing the electron-phonon coupling strength a The effective mass of the bipolaron M＊ increases rapidly with increasing the relative distance r between two electrons when r is smaller, and it reaches a maximum at r ≈ 4.05rp, while after that, 34＊ decreases slowly with increasing r. The effective mass of the bipolaron M＇ decreases with increasing the temperature. The electron-phonon coupling strength a markedly influences the changes of mean number of LO phonons and the effective mass M＊ with the relative distance r and the temperature parameter y.