Resonant acoustic calorimetry of the interaction of laser radiation with nonlinear-optical crystals

Resonant acoustic calorimetry technique gives the opportunity to measure the crystal temperature during linear and nonlinear interaction of the laser radiation with crystals. It is based on the registration of the piezoelectric resonance frequency change caused by the interaction of the laser radiation with crystals. Piezoelectric resonance is observed by measuring the dependence of the sample electrical impedance on the external electric field frequency. It is shown that inhomogeneous crystal heating can be characterized by the equivalent temperature depending on the laser power. Crystal equivalent temperature can be directly determined from the measured piezoelectric resonance frequency.