The generation of extreme ultraviolet (XUV) pulses with circular or elliptical polarization by using table-top sources is currently a hot research topic, due to the important applications of these pulses. Circularly-polarized XUV radiation is extensively used for the analysis of the structural, electronic and magnetic properties of matter employing various experimental techniques: e.g., photoelectron circular dichroism for the investigation of chiral molecules, angle-resolved photoemission spectroscopy (ARPES) with circularly-polarized XUV pulses and X-ray magnetic circular dichroism (XMCD) spectroscopy for the study of magnetic materials. Synchrotron radiation is typically used for these applications. Table-top sources of pulses in the XUV with circular polarization and ultrashort duration (from tens of femtoseconds to hundreds of attoseconds) would produce a boost for the investigation of ultrafast processes involved in chirality-sensitive light–matter interactions. Based on previously implemented strategies, we present the generation of laser driven intense short-pulse coherent XUV radiation of controlled polarization and tunability in photon energy. The output spectrum of this highly-elliptical HHG radiation can be tuned for an energy range of ∆E 150meV in the spectral range of 20 eV with energy per pulse E^XUV 400 nJ at the source. This is to our knowledge the highest energy content per pulse in laser driven highly-elliptical/circularly polarized XUV radiation. Polarimetric investigation of this XUV radiation is also presented. The demonstrated energy values (along with tight XUV focusing geometries) are sufficient to induce nonlinear processes. Our results challenge current perspectives regarding ultrafast investigations of chiral phenomena in the XUV spectral region. Some applications of this unique beamline will be proposed.

References

1. E. Vassakis , I. Orfanos , I. Liontos, E. Skantzakis, Generation of Energetic Highly Elliptical Extreme Ultraviolet Radiation. Photonics 2021, 8, 378. https://doi.org/10.3390/photonics8090378

2. E. Vassakis, S. Madas, L. Spachis, I. Orfanos, S. Kahaly, M. Upadhyay Kahaly, P. Tzallas, D. Charalambidis, E. Skantzakis, On the tunability of energetic highly-elliptical higher harmonics generated by intense two-color counter rotating laser fields. arXiv:2202.09521