In this paper, experimental photoluminescence (PL) and piezoelectric photothermal (PPT) spectra of selected II–VI binary crystals are presented and analyzed. The quantitative analysis of the photothermal spectra was performed using a modified and extended Jackson–Amer model. The values of the bandgap energies of investigated semiconductors were computed from the PT amplitude and phase spectra. From the temperature dependence of the exciton emission so-called “excitonic energy gaps” have been determined. It follows from the theory that the exciton binding energy is the difference of these two values of energy gaps derived from PPT and PL spectroscopy.

This paper describes the design and optimisation of the photoacoustic (PA) cell for nondestructive PA spectroscopy. The results of numerical calculations of the acoustic properties of the PA cell are compared with experimental measurements with respect to the frequency response and the quality factor of the cell. The method of designing and optimising of the PA cell is presented. Advantages and disadvantages of this study are discussed.