极性晶体中慢激子极化势的性质

本文讨论极性晶体中慢激子极化势的性质,把作者过去的工作推广到电子和空穴质量不相等的情形。采用微扰法,在忽略反冲效应中不同波矢的声子之间的相互作用后,计算了二级近似的波函数。由此进一步计算了慢激子的极化电势,发现:激子的极化电势受到纵光学声子的屏蔽,其屏蔽长度与纵光学声子的频率、激子的质量的平方根成反比;极化电势和电子、空穴质量有关,在电子、空穴质量比等于1时最小。 关键词：

THE ELECTROSTATIC POTENTIAL OF SLOW EXCITON IN A POLAR CRYSTAL

In this paper, the properties of a slow exciton in a polar crystal are discussed. The previous work of the author is generalized to the case that the electron mass is not equal to the hole mass. A perturbation method developed by Haga is used. In the approxiamation that the interaction of phonons of different wave vector in the recoil effect can be neglected, the wave function in the second order approxiamation is derived, and the electrostatic pontential is also calculated.