Schilt, StephaneThévenaz, Luc2008-09-292008-09-292008-09-29200610.1016/j.infrared.2005.09.001https://infoscience.epfl.ch/handle/20.500.14299/29909WOS:0002383981000088746A 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 first- and second-harmonic photoacoustic signals produced by a current-modulated semiconductor laser. Combined intensity- and wavelength-modulation is considered with arbitrary phase shift. Experimental results obtained when probing a CO2 absorption line with a 2-μm distributed feedback laser are presented and validate the relevance of the reported model. © 2005 Elsevier B.V. All rights reserved.Photoacoustic spectroscopyModulationTrace analysisDistributed feedback lasersSemiconductor lasersEnergy absorptionHarmonic analysisPhase shiftLasersFeedbacktext::journal::journal article::research article