Wavelength modulation photoacoustic spectroscopy: Theoretical description and experimental results
نویسندگان
چکیده
A theoretical description of photoacoustic spectroscopy generated by wavelength modulation of a semiconductor laser source is reported for a Lorentzian absorption line. This model describes the firstand second-harmonic photoacoustic signals produced by a current-modulated semiconductor laser. Combined intensityand wavelength-modulation is considered with arbitrary phase shift. Experimental results obtained when probing a CO2 absorption line with a 2-lm distributed feedback laser are presented and validate the relevance of the reported model. 2005 Elsevier B.V. All rights reserved. PACS: 42.55.Px; 42.60.Fc; 42.62.Fi
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