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arXiv · 1403.4631

High photon flux table-top coherent extreme ultraviolet source

Steffen Hädrich·Arno Klenke·Jan Rothhardt·Manuel Krebs·Armin Hoffmann·Oleg Pronin·Vladimir Pervak·Jens Limpert·Andreas Tünnermann
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Abstract

High harmonic generation (HHG) enables extreme ultraviolet radiation with table-top setups. Its exceptional properties, such as coherence and (sub)-femtosecond pulse durations, have led to a diversity of applications. Some of these require a high photon flux and megahertz repetition rates, e.g. to avoid space charge effects in photoelectron spectroscopy. To date this has only been achieved with enhancement cavities. Here, we establish a novel route towards powerful HHG sources. By achieving phase-matched HHG of a megahertz fibre laser we generate a broad plateau (25 eV - 40 eV) of strong harmonics, each containing more than $10^{12}$ photons/s, which constitutes an increase by more than one order of magnitude in that wavelength range. The strongest harmonic (H25, 30 eV) has an average power of 143 $μ$W ($3\cdot10^{13}$ photons/s). This concept will greatly advance and facilitate applications in photoelectron or coincidence spectroscopy, coherent diffractive imaging or (multidimensional) surface science.

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Steffen Hädrich, Arno Klenke, Jan Rothhardt, Manuel Krebs, Armin Hoffmann, Oleg Pronin, Vladimir Pervak, Jens Limpert, Andreas Tünnermann. 2014-03-18. High photon flux table-top coherent extreme ultraviolet source. https://doi.org/10.1038/nphoton.2014.214

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