Cascade pumping of GaSb-based type-Ⅰ quantum well diode lasers

摘要

Cascade GaSb-based type-Ⅰ quantum well diode lasers were designed and fabricated. Cascade pumping was achieved utilizing efficient interband tunneling through "leaky" window in band alignment at GaSb/InAs heterointerface. The 100% efficient carrier recycling between stages was confirmed by twofold increase light-current characteristics slope of two-stage 2.4 - 3.3 μm cascade lasers as compared to reference single-stage devices. Moderate internal optical loss increase was observed in cascade lasers with interband injector located near the optical mode peak. Cascade pumping scheme increased the continuous wave output power of room temperature operated 2.4 - 3 μm semiconductor lasers and led to improved power conversion efficiency.