Laser induced modification of the thermo-optical properties of Nd:YAG crystal determined by thermal lens technique

A Nd:YAG single crystal thin disc sample was irradiated by 200 pulses of 193 nm wavelength ArF laser at 35 mJ cm−2 laser fluence and 50 Hz repetition rate. The UV–Vis-NIR spectrum of the sample showed that the transmission has increased and the crystal quality has improved after the irradiation. A time-resolved mode mismatch dual beam thermal lens setup was used to determine thermo-optical properties of the Nd:YAG crystal before and after the irradiation. The results of the thermal lens (TL) experiment showed the thermal diffusion coefficient has been increased from 0.0459 to 0.0612 cm2 s−1. In addition, TL signal values of the irradiated crystal were obtained less than half of the TL signal values of un-irradiated crystal. The results show that low dose ArF laser irradiation improves thermo-optical properties of the Nd:YAG laser crystal.