Generation of micro-Joule level coherent quasi-continuum extreme ultraviolet radiation using multi-cycle intense laser-atom interactions

TL;DR

This work reports on a compact, high-intensity, broadband XUV source generated via multi-cycle laser-atom interactions, supporting isolated attosecond pulses suitable for advanced ultrafast experiments.

Contribution

The paper introduces a novel collinear polarization gating method enabling the generation of intense, broadband, quasi-continuum XUV radiation with isolated attosecond pulses from a multi-cycle infrared laser.

Findings

XUV spectral range of 17-32 eV achieved

Pulse durations of 0.4 to 1.3 fs demonstrated

High pulse energy (~1 μJ) confirmed by two-photon ionization

Abstract

In the present work we report on the current progress of the recently constructed GW attosecond extreme ultraviolet (XUV) source developed at the Institute of Electronic Structure and Laser of the Foundation for Research and Technology-Hellas (I.E.S.L-FO.R.T.H.). By the implementation of a compact-collinear polarization gating arrangement, the generation of a broadband, coherent XUV quasi-continuum produced by the interaction of a many-cycle infrared field with a gas phase medium is achieved. The spectral width of the XUV emission generated in Xenon, is spanning in the range of 17-32 eV and can support isolated pulses of duration in the range from 0.4 fs to 1.3 fs and pulse energy in the 1 {\mu}J level.Theoretical calculations, taking into account the experimental conditions of this work, are supporting the observations, offering also an insight regarding the temporal profile of the emitted radiation. Finally, the high intensity of the produced XUV pulses has been confirmed by investigating the two-XUV-photon double ionization process of Argon atoms. The demonstrated results inaugurate the capability of the beamline to produce intense isolated attosecond pulses towards their exploitation in studies of non-linear XUV processes, attosecond pulse metrology and XUV pump XUV probe experiments.