二维量子点中极化子的自旋弛豫

摘要

在考虑Rashba自旋一轨道耦合的条件下,采用二次幺正变换和变分方法研究了二维抛物量子点中由于电子与体纵光学声子的耦合作用形成的极化子在基态Zeeman分裂能级上的自旋弛豫过程.这一过程主要是通过吸收或发射一个形变势或压电声学声子完成.具体分析了强、弱耦合两种极限下极化子自旋弛豫率与外磁场、量子点半径、Landau因子参数、Rashba自旋轨道耦合参数的变化关系.%We theoretically investigate the spin relaxation of polaron,which arises from the electron interactions with the longitudinal optical phonon between the sublevel Zeeman splitting of the polaron ground state by using the vibrational and the unitary transformation methods in a two-dimensional quantum dot,where the Rashba spin-orbital coupling is taken into account.In fact,this process occurs by means of the absorption（or emitting） of a deformation potential acoustic phonon（or a piezoelectric one）.The relaxation rate dependences of the magnetic,the quantum dot radius,the lander parameter,the Rashba spin-orbital coupling parameter are studied under the conditions of the strong coupling limitation and the weak one.