Room temperature midinfrared electroluminescence from InAs quantum dots

We demonstrate room temperature midinfrared electroluminescence from intersublevel transitions in self-assembled InAs quantum dots. The dots are grown in GaAs/AlGaAs heterostructures designed to maximize current injection into dot excited states while preferentially removing electrons from the ground states. As such, these devices resemble quantum cascade lasers. However, rigorous modeling of carrier transport through the devices indicates that the current transport mechanism for quantum dot active regions differs from that of quantum-well-based midinfrared lasers. We present the calculated energy states and transport mechanism for an intersublevel quantum dot emitter, as well as experimental electroluminescence data for these structures.