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Generation of bright phase-matched circularly-polarized extreme ultraviolet high harmonics



Justin M. Shaw, Patrik Grychtol, Dmitriy Zusin, Ronny J. Knut, Tenio Popmintchev, Hans T. Nembach, Avner Fleischer, Henry Kapteyn, Margaret Murnane, Ofer Kfir, Oren Cohen


Circularly-polarized extreme UV and X-ray radiation provides valuable access to the structural, electronic and magnetic properties of materials. To date, this capability was available only at large-scale X-ray free-electron lasers or synchrotrons. Here we demonstrate the first bright, phase-matched, extreme UV circularly-polarized high harmonics and use this new light source for magnetic circular dichroism measurements at the M-shell absorption edges of cobalt. We show that phase matching of circularly-polarized harmonics is unique and robust, producing a photon flux comparable to the linearly polarized high harmonic sources that have been used very successfully for ultrafast element-selective magneto-optic experiments. Our work thus represents another milestone on the way towards element-specific imaging and spectroscopy of multiple elements simultaneously in magnetic and other chiral media with very high spatial and temporal resolution, all on a tabletop.
Nature Photonics


High-harmonic generation, x-ray spectroscopy, magnetism, xmcd, x-ray magnetic circular dichroism


Shaw, J. , Grychtol, P. , Zusin, D. , Knut, R. , Popmintchev, T. , Nembach, H. , Fleischer, A. , Kapteyn, H. , Murnane, M. , Kfir, O. and Cohen, O. (2014), Generation of bright phase-matched circularly-polarized extreme ultraviolet high harmonics, Nature Photonics, [online], (Accessed July 24, 2024)


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Created December 8, 2014, Updated November 10, 2018