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Indexed by:期刊论文

Date of Publication:2018-10-15

Journal:OPTICS LETTERS

Included Journals:SCIE

Volume:43

Issue:20

Page Number:5038-5041

ISSN No.:0146-9592

Abstract:An all-optical photoacoustic spectroscopy based on lock-in white-light interferometry is proposed for trace gas detection. The cavity length of the fiber-optic Fabry-Perot cantilever microphone is demodulated by a high-speed white-light interferometer, whose spectral sampling is synchronously triggered by a phased locked signal. To improve the signal-to-noise ratio, the demodulated digital photoacoustic signal is further processed by a specially designed virtual lock-in amplifier. The designed photoacoustic spectrometer has been tested for trace acetylene (C2H2) detection in the near-infrared region. The normalized noise equivalent absorption coefficient for C2H2 is achieved to be 1.1 x 10(-9) cm(-1) W Hz(-1/2). (C) 2018 Optical Society of America