Impact of Hole Dynamics on InAs/GaAs Quantum Dot Lasers.

In this paper, the internal mechanism of the QD has been studied, based on the separate electron-hole dynamics. For the first time, we have established the numerical model of InAs/GaAs QD laser by using four-levels rate equations model (4LREM) include different processes ,recombination, capture, escape, for holes and electrons. Then, the (4LREM) is solved numerically using fourth-order Runge-Kutta method. Gain characteristic and the output power of the QD laser have been studied respectively. The results show that the QD laser has small threshold current for ground state (GS), excited state (ES) and continues state (CS). The simulation results are in accordance with the experimental results, which prove that the rate equation model can simulate various properties of QD laser perfectly. The work is beneficial to QD laser research. As a simplified model of QD laser, both homogeneous and inhomogeneous broadening effects are ignored, and the model can be further improved.