The objective of the proposed effort is to develop high-performance mid-wave infrared (MWIR) Quantum Cascade Lasers (QCLs) with a large area aperture achieved through a surface emission architecture. Compared to a standard edge emitting laser, the extended aperture of the surface emitting laser reduces the optical power density by over two orders of magnitude, thus eliminating the failure mechanism related to catastrophic optical breakdown at the laser facet. This can be achieved in compact devices which can be produced at reduced cost. In this proposed project, the surface emission architecture will first be optimized with numerical modeling for optimal efficiency and near diffraction limited output. The numerical modeling will be verified through proof of concept verification of the proposed device. The potential for power scaling will also be explored with the goal of achieving at least 20 W of output power in continuous operation.
Benefit: This compact and high performance laser technology has four primary benefits. First, by eliminating high optical power facet damage, greater reliability is feasible, lowering the total cost of ownership for a laser system. Second, the surface emitting modality allows for novel power scaling architectures, which allows for significant higher output power per device. Third, a reduced output beam divergence will simplify device packaging. Fourth, the device does not rely on cleaved facets like a standard edge-emitting laser, which means it can be produced and pre-screened on a wafer level. This significantly increase yield and reduces overall packaging and testing costs. Overall, this new laser architecture will enhance DoD applications in the areas of Directed Infrared Countermeasures (DIRCM), advanced chemicals sensors, and Laser Detection and Ranging (LIDAR). The commercial sector can also benefit in a similar fashion in areas such as environmental monitoring and noninvasive medical screening.
Keywords: MWIR, MWIR, Quantum Cascade Laser, surface emitting laser, high power
