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) demonstrate a single-element, 4.6 micron-emitting quantum-cascade-laser (QCL) with > 40 % continuous-wave (CW) wallplug efficiency (WPE) at room temperature; (2) perform a comprehensive simulation to achieve a design for a monolithic QCL operating in a single spatial mode to 10 W CW output power; 3) perform a thermal-management analysis for the designed 10 W CW single-spatial-mode QCL; 4) demonstrate single-spatial-mode CW operation to watt-range output powers; 5) demonstrate and deliver a ~ 4.6 micron-emitting prototype QCL of 40 % maximum CW WPE and high-beam quality (M2 < 1.5) to at least 10 W CW output power. The QCLs will be designed to substantially suppress carrier leakage out of their active regions and achieve fast carrier extraction from their active regions. The QCLs packaging will be optimized for 10 W CW room-temperature operation. As a result, 4.6-micron wavelength QCLs operating in a single spatial mode with 40 % CW wallplug efficiency and to at least 10 W CW output power will be realized.