Photoacoustic spectra of CdS detected from the unilluminated surface

摘要

The photoacoustic spectra detected from the reverse side of a CdS single crystal have been studied. Photoacoustic amplitude detected from the unilluminated surface is noticeably influenced by the sample absorption, namely the sample thickness, and there is an optimum value of the sample thickness. The phase variations in this method considerably depend on incident light wavelength, compared to the usual photoacoustic spectroscopy (PAS). The Rosencwaig and Gersho theory for the usual PAS has been extended to the reverse side detection of PAS. These theoretical results agree with experimental values, and predict the importance of the phase study in this method.