随机层厚分布的半导体超晶格光荧光对温度的依赖关系

The Dependence of Photoluminescence on Temperature in GaAs/AlAs Superlattices with Random Layer Thicknesses

本文提出热激活辐射过程和 Ｂｅｒｔｈｅｌｏｔ－型的非辐射复合过程互相竞争的简单模型解释无序半导体超晶格的光荧光防温度变化行为．预言了当温度升高荧光衰变时间在某一温度附近快速下降；获得了在高温时较大无序度的半导体超晶格比较小无序度的半导体超晶格荧光强，在低温时情况相反；且荧光峰随温度变化存在一个最大值．理论结果与实验观察到的无序半导体超晶格荧光行为一致．

A simple model, involving the competition between an activated process and a Berthelot- type nonradiative process, is used to explain the temperature dependence of the photoluminescence (PL)behavior of disordered semiconductor superlattices. We predict that at 10K the PL decay time quickly decreases with increasing temperature. We also obtain that, at low temperature, the PL intensity of the disordered sedriconductor superlattice with less disordered degree is larger thanthat of the disordered semiconductor superlattice with larger disordered degree and at high temperature the case is on the contrary; the PL intensity has a maximum at a certain temperature. These results of the disordered semiconductor superlattice are in agreement with that observed by experiments.