The radiative quantum efficiency of doped Nd 3+ ion in soda-lime glass was calculated by laser photoacoustic spectroscopy. The variation of the intensity of the incident light signal with the frequency of the modulation is in agreement with the theory of the photoacoustic effect. The determination of the radiative quantum efficiency in this material is described using two lengths of where different as a function of a fixed modulation frequency. The measured value η = 0.87 +/- 0.04 is compared with those obtained by other methods
