A Spectrally Resolved Single-Shot Wavefront Sensor for Broadband High-Harmonic Generation Sources

High-harmonic generation (HHG) sources are becoming a mature table-top source of coherent extreme-ultraviolet (XUV) and soft-X-ray radiation, and are being used in many applications such as time-resolved spectroscopy, nanoscale imaging and even nonlinear XUV optics. For many such applications, accurate knowledge of the wavefront is important to correctly interpret experimental results. While several solutions exist to measure wavefronts for visible and XUV radiation [1,2], HHG sources pose a specific challenge because of their intrinsically ultra-broadband spectral widths, combined with often significant pulse-to-pulse variability because of the highly nonlinear generation mechanism. Therefore, an HHG wavefront sensor should ideally provide both spectral resolution and single-shot measurement capability.