Single Mode Type-I QC DFB Lasers at 10 Micron for Gas Sensing

70560 New mid-infrared laser sources, such as the Quantum Cascade (QC) laser, are necessary to develop advanced and inexpensive gas sensing systems to monitor industrial-related chemical processes, including combustion and pollution effluent. This project will develop QC lasers with emission wavelengths near 10 ¿m, suitable for sensing ammonia, volatile organic hydrocarbons, and other important substances. These lasers will have the tunability and narrow linewidth required for spectroscopic applications. Phase I will concentrate on device design, simulation, and modeling, along with developing processing procedures, especially grating fabrication. The parameters affecting laser performance will be identified and characterized. Initially simple broad-area Fabry-Perot devices will be fabricated, and then ridge-waveguide distributed feedback lasers will be made. Phase II will optimize the fabrication procedures developed in Phase I. Commercial Applications and Other Benefits as described by the awardee: The QC lasers should have application to 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.