Continuously-tunable monochromatic HHG source for applications

High-order harmonic generation (HHG) is a tabletop source of VUV radiation with many applications limited by a necessity for a specific photon energy and a monochromatized spectrum. The approach of using grating monochromators is not applicable for photon-hungry applications due to the high losses and pulse lengthening. We present experimental results of a wavelength-tunable monochromatic HHG source developed to tackle this challenge. We demonstrate this method using the L1 Allegra broadband OPCPA laser system at ELI-Beamlines and its conversion to UV used to pump the HHG.