GaAs薄膜的瞬态光致折射率变化研究

Transient optical induced refractive index changein CaAs film

利用飞秒瞬态反射谱和透射谱，研究了ＧａＡｓ薄膜的瞬态光致折射率变化，观察到光致折射率的一个超快弛豫过程和一定激发浓度下的瞬态光致吸收增加现象，用受激载流子引起的带填充和能隙收缩解释了这些现象。

In this paper, the transient optical induced refractive index change in GaAs film is studied using femtosecond transmission and reflection spectroscopy. An ultrafast relaxation process of the optical induced refractive index is observed , with optical in- duced absorption increase at specific excitation density. All this can be interpreted with the help of the band filling and the bandgap shrinking effects of the excited carriers.