Continuous-Wave Thermoelectric-Cooled 5.26 Micron QC Laser for Chemical Sensing

70559 New mid-infrared laser sources, such as the Quantum Cascade (QC) laser, are necessary to develop advanced and inexpensive gas sensing systems to monitor chemical processes, including combustion and pollution effluent, for national security applications. This project will develop continuous-wave QC lasers that can be operated at temperatures accessible with a thermoelectric cooler, making these devices suitable for sensing applications. Advanced thermal management techniques, including junction side down mounting, diamond heat sinks, and advanced epitaxial design will be applied to optimize the high temperature performance of the device. Phase I will demonstrate a working cw QC laser with thermoelectric cooling at 5.26 ¿m wavelength. The device will be designed, simulated, and modeled, and processing procedures, especially narrow ridge waveguide fabrication, will be developed. Device performance will be identified and characterized, with an eye towards developing a Phase II work plan that will optimize fabrication and packaging procedures. Commercial Applications and Other Benefits as described by the awardee: Commercial applications for the laser should include combustion chamber monitoring and combustion process control, sensitive monitoring of pollution effluent from petrochemical plants and other industrial facilities, high-sensitivity monitoring of potentially harmful chemicals to ensure worker safety, and monitoring of chemical processing conditions for yield enhancement.