A novel method of detecting the spectral width and wavelength of extreme ultraviolet (XUV) pulses with a minimum number of experimental tools is demonstrated. The method relies on the photoionization probability of an atom as a function of the electric field. A tunable laser source in the XUV is used that is based on higher-harmonic generation of the frequency-doubled output of a 50-fs Ti:sapphire laser. The bandwidth and the wavelength of the seventh harmonic (~57nm) are detected with Ne, and the resolving power is λ/Δλ=10<sup>5</sup>.
© 2001 Optical Society of America
J. B. M. Warntjes, A. Gürtler, A. Osterwalder, F. Rosca-Pruna, M. J. J. Vrakking, and L. D. Noordam, "Atomic spectral detection of tunable extreme ultraviolet pulses," Opt. Lett. 26, 1463-1465 (2001)