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量子阱的光致发光现象，为电光器件的应用奠定基础。单CdSe/ZnS量子点光致发光闪烁的激发密度依赖性表明双激子的产生是trion态的前兆，而不是OFF态的前兆。此外，太赫兹电场依赖性和GaAs量子阱PL闪光强度的弛豫动力学表明，太赫兹脉冲的强电场在太赫兹脉冲的1皮秒周期内电离杂质态，并从AlGaAs层中含有杂质态的巨大储层中释放载流子。

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.