Characterization of a swept external cavity quantum cascade laser for rapid broadband spectroscopy and sensing.

The performance of a rapidly swept external cavity quantum cascade laser (ECQCL) system combined with an open-path Herriott cell was evaluated for time-resolved measurements of chemical species with broad and narrow absorption spectra. A spectral window spanning 1278 - 1390 cm(-1) was acquired at a 200 Hz acquisition rate, corresponding to a tuning rate of 2x10(4) cm(-1)/s, with a spectral resolution of 0.2 cm(-1). The capability of the ECQCL to measure < 100 ppbv changes in nitrous oxide (N(2)O) and 1,1,1,2-tetrafluoroethane (F134A) concentrations on millisecond timescales was demonstrated in simulated plume studies with releases near the open-path Herriott cell. Absorbance spectra measured using the ECQCL system exhibited noise-equivalent absorption coefficients of 5x10(-9) cm(-1)Hz(-1/2). For a spectrum acquisition time of 5 ms, noise-equivalent concentrations (NEC) for N(2)O and F134A were measured to be 70 and 16 ppbv respectively, which improved to sub-ppbv levels with averaging to 100 s. Noise equivalent column densities of 0.64 and 0.25 ppmv × m in 1 sec are estimated for N(2)O and F134A.

[1]  Mark C. Phillips,et al.  Hyperspectral microscopy of explosives particles using an external cavity quantum cascade laser , 2012 .

[2]  I. Petersen,et al.  Pulsed quantum cascade laser-based CRDS substance detection: real-time detection of TNT. , 2012, Optics express.

[3]  T. L. Myers,et al.  External cavity quantum cascade laser for quartz tuning fork photoacoustic spectroscopy of broad absorption features. , 2007, Optics letters.

[4]  M. Taubman.  Low-noise high-performance current controllers for quantum cascade lasers. , 2011, The Review of scientific instruments.

[5]  Mark Norman,et al.  Detection of chemical clouds using widely tunable quantum cascade lasers , 2015, Defense + Security Symposium.

[6]  C. Kumar N. Patel,et al.  External cavity quantum cascade lasers with ultra rapid acousto-optic tuning , 2015 .

[7]  B. Bernacki,et al.  Spectral and angular dependence of mid-infrared diffuse scattering from explosives residues for standoff detection using external cavity quantum cascade lasers , 2012 .

[8]  John Tulip,et al.  Real-time monitoring of benzene, toluene, and p-xylene in a photoreaction chamber with a tunable mid-infrared laser and ultraviolet differential optical absorption spectroscopy. , 2011, Applied optics.

[9]  Erik E. Josberger,et al.  Infrared near-field spectroscopy of trace explosives using an external cavity quantum cascade laser. , 2013, Optics express.

[10]  J. Röpcke,et al.  High resolution spectroscopy of silane with an external-cavity quantum cascade laser: Absolute line strengths of the ν3 fundamental band at 4.6μm , 2015 .

[11]  Gerard Wysocki,et al.  Chirped laser dispersion spectroscopy with harmonic detection of molecular spectra , 2012, Applied Physics B.

[12]  M. Zahniser,et al.  High precision measurements of atmospheric nitrous oxide and methane using thermoelectrically cooled mid-infrared quantum cascade lasers and detectors. , 2004, Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.

[13]  T. L. Myers,et al.  Real-time trace gas sensing of fluorocarbons using a swept-wavelength external cavity quantum cascade laser. , 2014, The Analyst.

[14]  Gerard Wysocki,et al.  QEPAS based detection of broadband absorbing molecules using a widely tunable, cw quantum cascade laser at 8.4 mum. , 2007, Optics express.

[15]  Manu Prasanna,et al.  Sub-parts-per-billion level detection of dimethyl methyl phosphonate (DMMP) by quantum cascade laser photoacoustic spectroscopy. , 2008, Applied optics.

[16]  Gerard Wysocki,et al.  External-cavity quantum cascade lasers with fast wavelength scanning , 2010 .

[17]  M. Phillips,et al.  Intracavity sensing via compliance voltage in an external cavity quantum cascade laser. , 2012, Optics letters.

[18]  Frank K. Tittel,et al.  Single-QCL-based absorption sensor for simultaneous trace-gas detection of CH4 and N2O , 2014 .

[19]  Damien Weidmann,et al.  Middle infrared active coherent laser spectrometer for standoff detection of chemicals. , 2013, Optics letters.

[20]  Mark C. Phillips,et al.  Use of external cavity quantum cascade laser compliance voltage in real-time trace gas sensing of multiple chemicals , 2015, SPIE OPTO.

[21]  S. Corzine,et al.  Widely tunable mode-hop free external cavity quantum cascade lasers for high resolution spectroscopy and chemical sensing , 2008 .

[22]  H. Schenk,et al.  Widely tunable quantum cascade lasers for spectroscopic sensing , 2015, SPIE OPTO.

[23]  N. P. Sanchez,et al.  Simultaneous atmospheric nitrous oxide, methane and water vapor detection with a single continuous wave quantum cascade laser. , 2015, Optics express.

[24]  Frank K. Tittel,et al.  Atmospheric ammonia measurements in Houston, TX using an external-cavity quantum cascade laser-based sensor , 2010 .

[25]  F. Molero,et al.  Broadband standoff detection of large molecules by mid-infrared active coherent laser spectrometry. , 2015, Optics express.

[26]  Kang Sun,et al.  Compact and portable open-path sensor for simultaneous measurements of atmospheric N2O and CO using a quantum cascade laser. , 2012, Optics express.

[27]  Xuncheng Liu,et al.  Jet-cooled infrared spectra of molecules and complexes with a cw mode-hop-free external-cavity QCL and a distributed-feedback QCL , 2011 .

[28]  Gerard Wysocki,et al.  Chirped Laser Dispersion Spectroscopy for Remote Open-Path Trace-Gas Sensing , 2012, Sensors.

[29]  B. Mizaikoff,et al.  Breath analysis with broadly tunable quantum cascade lasers. , 2013, Analytical chemistry.

[30]  A. Robinson,et al.  Trace gas emissions from combustion of peat, crop residue, domestic biofuels, grasses, and other fuels: configuration and Fourier transform infrared (FTIR) component of the fourth Fire Lab at Missoula Experiment (FLAME-4) , 2014 .

[31]  Ronald K. Hanson,et al.  Simultaneous sensing of temperature, CO, and CO2 in a scramjet combustor using quantum cascade laser absorption spectroscopy , 2014 .

[32]  Erik R. Deutsch,et al.  Standoff detection of chemical and biological threats using miniature widely tunable QCLs , 2015, Defense + Security Symposium.

[33]  T. Johnson,et al.  Gas-Phase Databases for Quantitative Infrared Spectroscopy , 2004, Applied spectroscopy.

[34]  Rolf Aidam,et al.  Broadband-tunable external-cavity quantum cascade lasers for the spectroscopic detection of hazardous substances , 2013, Photonics West - Optoelectronic Materials and Devices.