Super-Efficient Mid-Infrared Quantum Cascade Lasers with Continuous-Wave Wall-Plug Efficiencies in Excess of 40%

The technical objectives of this proposal are: 1) perform a comprehensive simulation of 4.6 micron-emitting quantum cascade lasers (QCLs) with suppressed carrier leakage and efficient carrier extraction to design a device with pulsed wall-plug efficiency > 40 %; 2) perform a thermal analysis of 4.6 micron-emitting QCLs to design structures capable of operating with > 40 % continuous-wave (CW) wall-plug efficiency at room temperature; 3) establish the key material- and device-related parameters for high-performance, 4.6 micron-emitting QCLs. QCLs will be designed to substantially suppress carrier leakage out of their active regions and achieve fast carrier extraction from their active regions. Novel thermal management approaches will be designed in order to minimize the overall thermal conductance of the packaged device. The design will be for over 40 % CW wall-plug efficiency at 4.6-micron wavelength, in a structure to eventually be suitable for multi-watt CW operation with a high-quality beam pattern.