High-power/low-threshold type-II interband cascade mid-IR laser-design and modeling

We present an optimized design and detailed numerical simulations for a mid-IR type-II interband InGaSb QW cascade laser (T2ICL) with InAs-In/sub 0.3/Ga/sub 0.7/Sb active quantum wells. It is shown that a 15-period T2ICL operating at 300 K and emitting at 3.15 μm should achieve a much higher differential quantum efficiency (maximum of 0.9 W/A per facet at 300 K) than conventional mid-IR bipolar injection lasers, and a threshold current density much lower than for the intersubband quantum cascade laser.