All femtosecond optical pump and X-ray probe: holey-axicon for free electron laser

V. Anand; J. Maksimovic; T. Katkus; S. H. Ng; O. Ulcinas; M. Mikutis; J. Baltrukonis; A. Urbas; G. Slekys; H. Ogura; D. Sagae; T. Pikuz; T. Somekawa; N. Ozaki; A. Vailionis; G. Seniutinas; V. Mizeikis; K. Glazebrook; J. P. Brodie; P. R. Stoddart; L. Rapp; A. V. Rode; E. G. Gamaly; S. Juodkazis

arXiv · 2005.14654

All femtosecond optical pump and X-ray probe: holey-axicon for free electron laser

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Abstract

We put forward a co-axial pump(optical)-probe(X-rays) experimental concept and show performance of the optical component. A Bessel beam generator with a central 100 micrometers-diameter hole (on the optical axis) was fabricated using femtosecond (fs) laser structuring inside a silica plate. This flat-axicon optical element produces a needle-like axial intensity distribution which can be used for the optical pump pulse. The fs-X-ray free electron laser (X-FEL) beam of sub-1 micrometer diameter can be introduced through the central hole along the optical axis onto a target as a probe. Different realisations of optical pump are discussed. Such optical elements facilitate alignment of ultra-short fs-pulses in space and time and can be used in light-matter interaction experiments at extreme energy densities on the surface and in the volume of targets. Full advantage of ultra-short 10 fs X-FEL probe pulses with fs-pump(optical) opens an unexplored temporal dimension of phase transitions and the fastest laser-induced rates of material heating and quenching. A wider field of applications of fs-laser-enabled structuring of materials and design of specific optical elements for astrophotonics is presented.

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V. Anand, J. Maksimovic, T. Katkus, S. H. Ng, O. Ulcinas, M. Mikutis, J. Baltrukonis, A. Urbas, G. Slekys, H. Ogura, D. Sagae, T. Pikuz, T. Somekawa, N. Ozaki, A. Vailionis, G. Seniutinas, V. Mizeikis, K. Glazebrook, J. P. Brodie, P. R. Stoddart, L. Rapp, A. V. Rode, E. G. Gamaly, S. Juodkazis. 2020-05-24. All femtosecond optical pump and X-ray probe: holey-axicon for free electron laser. https://arxiv.org/abs/2005.14654

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