Design of quantum structure stripe lasersfor low threshold current

Abstract

In the case of quantum structure lasers, including quantum well, quantum wire and quantum box lasers, a simple method is presented to obtain optimal structure of the active region for a low threshold condition. A logarithmic description is used to describe the relationship between the material gain and the injected carrier density. Taking an InGaAs(P)/InP quantum-well laser and an InAs/GaAs self-assembled quantum box laser for example, the optimal condition to obtain the lowest threshold current are provided, including the number of quantum wells, the area density of quantum boxes, and the cavity length. The results show that a multi-stacked active region is very necessary to obtain a low threshold current for self-assembled quantum dot lasers.