LT-GaAs缺陷态对载流子的捕获特性

The Carrier Capturing Characteristics of Defects in LT-GaAs

采用宽频带飞秒脉冲泵浦 -探测方法测量了LT_GaAs中不同能态的光生载流子的超快捕获特性 ,发现随着载流子的过超能量增大 ,载流子的散射速率加快 ,而缺陷态对载流子的捕获速率 ,则与光生载流子的过超能量无关 ,表明LT_GaAs缺陷态捕获电子主要为点缺陷深能级多声子无辐射捕获过程。

With the technique of broad_band pump_probe,the ultrafast capturing characteristics of photo_excited carriers in LT_GaAs were studied.It is found that the initial scattering and cooling rates of the excited carriers decrease as the excess energies of the carriers decrease, but the capturing rate of defects is independent of the excess energies.This reveals that the carriers are captured by the defects formed by anti_position AsGa.