Detailed characterization of pump-induced refractive index changes observed in Nd:YVO(4), Nd:GdVO(4) and Nd:KGW.

ABSTRACT

The refractive index changes which can be induced in the NdYVO(4), NdGdVO(4) and NdKGW high gain laser crystals, when their Nd(3+) laser active ions are pumped from their ground- to excited- energy levels, have been carefully measured and characterized. By using two complementary optical techniques based on pump-probe interferometry and transient diffraction grating, the electronic and thermal contributions to the observed refractive index variations have been accurately determined and successfully exploited to derive various parameters such as polarizability changes, thermo-optic coefficients and thermal diffusivities.