Autocorrelation measurement was demonstrated for the first time to our knowledge in the XUV region to measure the width of a high-order harmonic pulse. Two-photon ionization of rare gases was used as a nonlinear process for the autocorrelation measurement. The 27-fs pulse width that was obtained is, to our knowledge, the shortest in the XUV region.
© 1998 Optical Society of America
Y. Kobayashi, T. Sekikawa, Y. Nabekawa, and S. Watanabe, "27-fs extreme ultraviolet pulse generation by high-order harmonics," Opt. Lett. 23, 64-66 (1998)