Ultra-short-pulse high-average-power megahertz-repetition-rate coherent extreme-ultraviolet light source

High harmonic generation (HHG) enables coherent extreme-ultraviolet (XUV) radiation with ultra-short pulse duration in a table-top setup. This has already enabled plethora of applications. Nearly all these applications would benefit from high photon flux to increase the signal-to-noise ratio and decrease measurement times. In addition, shortest pulses are desired investigate fastest dynamics fields as diverse physics, biology, chemistry material sciences. this work, up-to-date most powerful XUV source 12.9 mW single line at 26.5 eV is demonstrated via HHG frequency-doubled post-compressed fibre laser. At same time sub-6 fs allows accessing ultrafast an order magnitude higher than previously demonstrated. concept will greatly advance facilitate science technology enable photon-hungry studies.