Studying and controlling photoluminescence blinking of quantum dots by using intense THz pulses

本研究的目的是研究和控制量子点或威尔斯阱的光致发光现象，为电光器件的应用做准备。单个CdSe/ZnS量子点的光致发光（PL）闪烁的激发密度依赖性表明双激子的产生是trion态而不是OFF态的前体。此外，太赫兹电场的依赖性和弛豫动力学的PL闪烁强度的GaAs量子威尔斯表明，太赫兹脉冲的强电场电离杂质态在1皮秒周期的太赫兹脉冲和释放载流子从一个巨大的水库包含杂质态的AlGaAs层。

The purpose of this study is studying and controlling the photoluminescence phenomena of quantum dots or wells, which has expected for the applications of electro-optic devices. The excitation density dependence of photoluminescence (PL) blinking of single CdSe/ZnS quantum dots indicates that the biexciton generation is a precursor of the trion state and not of the OFF state. Also, the THz electric field dependence and the relaxation dynamics of the PL flash intensity of GaAs quantum wells suggest that the strong electric field of the THz pulse ionizes impurity states during the one-picosecond period of the THz pulse and release carriers from a giant reservoir containing impurity states in the AlGaAs layers.