Nonlinear elliptical polarization rotation is used to improve the contrast of femtosecond pulses by several orders of magnitude. Using nonlinear induced birefringence in air, we produced cleaned pulses with an energy of a few hundreds of microjoules. This technique presents several major advantages, such as convenience and stability of the setup. We investigated the phase profile required for obtaining high-energy pulses. No phase distortion is observed, and the spatial quality of the beam is preserved.
© 2004 Optical Society of America
Aurélie Jullien, Frédérika Augé-Rochereau, Gilles Chériaux, Jean-Paul Chambaret, Pascal d'Oliveira, Thierry Auguste, and Franck Falcoz, "High-efficiency, simple setup for pulse cleaning at the millijoule level by nonlinear induced birefringence," Opt. Lett. 29, 2184-2186 (2004)