10 March 2016 Spectroscopic benzene detection using a broadband monolithic DFB-QCL array
Author Affiliations +
Proceedings Volume 9767, Novel In-Plane Semiconductor Lasers XV; 97671T (2016) https://doi.org/10.1117/12.2213696
Event: SPIE OPTO, 2016, San Francisco, California, United States
Abstract
Quantitative laser spectroscopic measurements of complex molecules that have a broad absorption spectra require broadly tunable laser sources operating preferably in the mid-infrared molecular fingerprint region. In this paper a novel broadband mid-infrared laser source comprising of an array of single-mode distributed feedback quantum cascade lasers was used to target a broadband absorption feature of benzene (C6H6), a toxic and carcinogenic atmospheric pollutant. The DFB-QCL array is a monolithic semiconductor device with no opto-mechanical components, which eliminates issues with mechanical vibrations. The DFB-QCLs array used in this work provides spectral coverage from 1022.5 cm-1 to 1053.3 cm-1, which is sufficient to access the absorption feature of benzene at 1038 cm-1 (9.64 μm). A sensor prototype based on a 76 m multipass cell (AMAC-76LW, Aerodyne Research) and a dispersive DFB-QCL array beam combiner was developed and tested. The Allan deviation analysis of the retrieved benzene concentration data yields a short-term precision of 100 ppbv/Hz1/2 and a minimum detectable concentration of 12 ppbv for 200 s averaging time. The system was also tested by sampling atmospheric air as well as vapors of different chemical products that contained traces of benzene.
© (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Rafał Lewicki, Rafał Lewicki, Mark Witinski, Mark Witinski, Biao Li, Biao Li, Gerard Wysocki, Gerard Wysocki, "Spectroscopic benzene detection using a broadband monolithic DFB-QCL array", Proc. SPIE 9767, Novel In-Plane Semiconductor Lasers XV, 97671T (10 March 2016); doi: 10.1117/12.2213696; https://doi.org/10.1117/12.2213696
PROCEEDINGS
7 PAGES


SHARE
Back to Top