title: Gas detection by correlation spectroscopy employing a multimode diode laser.
abstract: A gas sensor based on the gas-correlation technique has been developed using a multimode diode laser (MDL) in a dual-beam detection scheme. Measurement of CO(2) mixed with CO as an interfering gas is successfully demonstrated using a 1570 nm tunable MDL. Despite overlapping absorption spectra and occasional mode hops, the interfering signals can be effectively excluded by a statistical procedure including correlation analysis and outlier identification. The gas concentration is retrieved from several pair-correlated signals by a linear-regression scheme, yielding a reliable and accurate measurement. This demonstrates the utility of the unsophisticated MDLs as novel light sources for gas detection applications.
authors.affiliation: Department of Physics, Harbin Institute of Technology, Harbin 150001, China.
authors.forename: Xiutao
authors.initials: X
authors.lastname: Lou
authors.forename: Gabriel
authors.initials: G
authors.lastname: Somesfalean
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D002245:Carbon Dioxide / Q000032:analysis; D002248:Carbon Monoxide / Q000032:analysis; D005740:Gases / Q000032:analysis; D054023:Lasers, Semiconductor; D055095:Optics and Photonics / Q000295:instrumentation; D012815:Signal Processing, Computer-Assisted; D013057:Spectrum Analysis / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data
chemical_list: D005740:Gases; D002245:Carbon Dioxide; D002248:Carbon Monoxide