Wave-front correction and focal spot improvement of femtosecond laser beams have been achieved, for the first time to our knowledge, with a deformable mirror with an on-line single-shot three-wave lateral shearing interferometer diagnostic. Wave-front distortions of a 100-fs laser that are due to third-order nonlinear effects have been compensated for. This technique, which permits correction in a straightforward process that requires no feedback loop, is also used on a 10-TW Ti:sapphire–Nd:phosphate glass laser in the subpicosecond regime. We also demonstrate that having a focal spot close to the diffraction limit does not constitute a good criterion for the quality of the laser in terms of peak intensity.
© 1998 1998 Optical Society of America
Frédéric Druon, Gilles Chériaux, Jérôme Faure, John Nees, Marc Nantel, Anatoly Maksimchuk, Gérard Mourou, Jean Christophe Chanteloup, and Gleb Vdovin, "Wave-front correction of femtosecond terawatt lasers by deformable mirrors," Opt. Lett. 23, 1043-1045 (1998)