Center Interdisciplinaire de Recherche Ions Laser (CIRIL), UMR6637 CEA-CNRS-ENSICAEN et Université de Caen, 6 Bd. Maréchal Juin, F14050 Caen, France
Abstract:
An experiment has been performed for measuring a nonlinear refractive index that is due to the polarizability difference ΔP between excited (4T2) and ground (4A2) states in a Cr3+:LiSAF crystal at λ = 647 nm. The latter one is responsible for a population lensing effect which has been monitored by using the eclipsing Z-scan technique. We have performed a data analysis that allows to distinguish between thermal and population contributions to the lensing effect. We have found ΔP = 4.6 × 10?25 cm3 which is in a good agreement with our previous measurements with a different technique.