Temperature dependence of droop onset in optically pumped intrinsic InGaAs/InP heterostructures

Although conventional III-V compound semiconductors are often considered not to exhibit an efficiency droop, a pronounced low temperature droop was recently measured in AlGaInP/GaAs multi-quantum well structures. In this work, we investigate the efficiency droop in simple optically pumped lattice matched InGaAs/InP single well heterostructures to exclude charge transport related effects from the measurements. The results show that droop is present in this very simplistic setup and, furthermore, starts approximately at the same carrier density as in typical III-N structures. Our results suggest that in its most fundamental form, droop can be explained by Auger-like processes.