In the race toward attosecond pulses, for which high-order harmonics generated in rare gases are the best candidates, both the harmonic spectral range and the spectral phase have to be controlled. We demonstrate that multilayer extreme-ultraviolet chirped mirrors can be numerically optimized and designed to compensate for the intrinsic harmonic chirp that was recently discovered and that is responsible for temporal broadening of pulses. A simulation shows that an optimized mirror is capable of compressing the duration from ∼260 to 90 as. This new technique is an interesting solution because of its ability to cover a wider spectral range than other technical devices that have already been proposed to overcome the chirp of high harmonics.
© 2005 Optical Society of America
Anne-Sophie Morlens, Philippe Balcou, Philippe Zeitoun, Constance Valentin, Vincent Laude, and Sophie Kazamias, "Compression of attosecond harmonic pulses by extreme-ultraviolet chirped mirrors," Opt. Lett. 30, 1554-1556 (2005)