An experiment has been performed to find evidence and analyze a nonlinear diverging lensing effect occurring in a flash-lamp-pumped Cr<sup>3+</sup>:LiSAF laser. The effect is assigned to a refractive-index change of the material that is proportional to the Cr<sup>3+</sup>-excited ion population, the corresponding constant of proportionality being determined from the time variation of the laser-pulse far-field divergence.
© 2004 Optical Society of America
Nicolas Passilly, Michael Fromager, Kamel Ait-Ameur, Richard Moncorgé, Jean-Louis Doualan, Antoine Hirth, and Greg Quarles, "Experimental and theoretical investigation of a rapidly varying nonlinear lensing effect observed in a Cr3+:LiSAF laser," J. Opt. Soc. Am. B 21, 531-538 (2004)