Monolithic Beam-Combined Mid-Infrared Laser Array

Monolithic surface-emitting (SE) semiconductor lasers hold promise for significant advantages over edge-emitting lasers in terms of both reliable operation, scaling the CW single-mode output powers into the multi-watt range, and manufacturing cost. Grating-coupled (GC) surface emitters offer a path to achieving single-spatial-mode, single-frequency CW operation, with the added advantage that relatively high single-mode CW output powers can be obtained. The technical objectives of this proposal are: 1) Develop narrow-ridge, buried heterostructure surface-emitting (SE) QCLs for CW operation; (2) Integrate gratings into the Active Photonic Crystal (APC) QCL array for surface-emission; 3) Develop indium on diamond chip mounting for APC QCL arrays; 4) Characterize thermal management of packaged single and multi-element (APC) SE QCL devices: The goals are 1.5 W CW power and 15W average power, respectively; 5) Prototype demonstration of CW fully packaged SE single-element and array (APC) QCLs, which will be deliverables after completion of the program.