High performance, high temperature λ≈3.7 μm InGaAs/AlAs(Sb) quantum cascade lasers

We report the development of λ≈3.7 μm strain-compensated InGaAs/AlAs(Sb) quantum cascade lasers operating up to at least 400 K with high peak power and high wall plug efficiency in pulsed regime. We present a detailed comparison of the laser characteristics for devices containing AlAs barriers in the active region with those for devices of identical design but with AlAsSb barriers throughout. The devices with AlAs barriers show significantly superior performance with peak optical power of 2.6 W at 300 K decreasing to 1 W at 400 K, and threshold current densities of 3.3 and 8.2 kA/cm2 at 300 and 400 K, respectively.