The wave-front distortion of femtosecond laser pulses recorded with a Shack–Hartmann analyzer makes it possible to retrieve the nonlinear index of refraction of different glasses and the nonlinear phase shift induced during second-harmonic generation in <i>β</i>-barium borate (BBO) crystal versus the phase mismatch. It is shown that the nonlinear phase shift induced in a 2-mm-thick BBO crystal allows compensation for up to a 2π breakup-integral induced in a 4-cm fused-silica glass. The stability of the compensation is reported to be from 10 to 100 GW cm<sup>-2</sup>.
© 2004 Optical Society of America
Jean Pascal Caumes, Laurent Videau, Claude Rouyer, and Eric Freysz, "Direct measurement of wave-front distortion induced during second-harmonic generation: application to breakup-integral compensation," Opt. Lett. 29, 899-901 (2004)