Applied Physics B

, Volume 109, Issue 2, pp 359–366

Acetylene detection based on diode laser QEPAS: combined wavelength and residual amplitude modulation

Authors

    • Department of Electrical EngineeringThe Hong Kong Polytechnic University
  • W. Jin
    • Department of Electrical EngineeringThe Hong Kong Polytechnic University
    • Department of Opto-electronics Engineering, School of Instrument Science and Opto-electronics EngineeringBeiHang University
  • H. L. Ho
    • Department of Electrical EngineeringThe Hong Kong Polytechnic University
  • L. Qi
    • Department of Electrical EngineeringThe Hong Kong Polytechnic University
  • Y. H. Yang
    • Department of Opto-electronics Engineering, School of Instrument Science and Opto-electronics EngineeringBeiHang University
Article

DOI: 10.1007/s00340-012-5221-4

Cite this article as:
Cao, Y., Jin, W., Ho, H.L. et al. Appl. Phys. B (2012) 109: 359. doi:10.1007/s00340-012-5221-4

Abstract

Quartz-enhanced photoacoustic spectroscopy (QEPAS) is demonstrated for acetylene detection at atmospheric pressure and room temperature with a fiber-coupled distributed feedback (DFB) diode laser operating at ~1.53 μm. An efficient approach for gas concentration calibration is demonstrated. The effect of residual amplitude modulation on the performance of wavelength modulated QEPAS is investigated theoretically and experimentally. With optimized spectrophone parameters and modulation depth, a minimum detectable limit (1σ) of ~2 part-per-million volume (ppmv) was achieved with an 8.44-mW diode laser, which corresponds to a normalized noise equivalent coefficient (1σ) of 6.16 × 10−8 cm−1 W/Hz1/2.

Copyright information

© Springer-Verlag 2012