Analytical Investigation of Electrons Capture Time Effect on the Threshold Current Density Reduction in QD Spin-Lasers

In this paper, we solve numerically the rate equations governing the semiconductor spin with un-polarized and polarized laser field based on quantum dot active region in which Schottky tunnel barrier treats as the spin injector. We demonstrate simultaneously the effects of electron capture time, and injected current polarization on threshold current density reduction and normalized spin-filtering interval. The threshold current density reduction and normalized spin-filtering interval increases simultaneously with electrons capture time reduction and increase of injected current polarization. The maximum obtained threshold current density reduction and normalized spin-filtering interval values are0.353 and 0.90, respectively. We also calculate the spin-up optical gain and obtain the conditions for achieving optimum optical gain. The maximum obtained spin-up optical gain value is 17.70.