Grating configurations for the spectral selection of coherent ultrashort pulses in the extreme-ultraviolet

Abstract

The design and realization of grating instruments to handle and condition coherent ultrafast pulses in the extreme ultraviolet spectral region are discussed. The main application of such instruments is the spectral selection of high-order laser harmonics and free-electron-laser pulses in the femtosecond time scale. Broad-band monochromators require the use of diffraction gratings at grazing incidence. Here, we discuss two configurations useful for the realization of grating monochromator with ultrafast response: the single-grating design, applied to high-order laser harmonics, and the time-delay-compensated configuration with two gratings, applied to free-electron lasers.