TY - JOUR AU - Beye, M. AU - Schreck, S. AU - Sorgenfrei, F. AU - Trabant, C. AU - Pontius, N. AU - Schüßler-Langeheine, C. AU - Wurth, W. AU - Föhlisch, A. TI - Stimulated X-ray emission for materials science JO - Nature VL - 501 IS - 7466 SN - 1476-4687 CY - London PB - Macmillan28177 M1 - DESY-2014-02110 SP - 191 - 194 PY - 2013 N1 - © Macmillan Publishers Limited. AB - Resonant inelastic X-ray scattering and X-ray emission spectroscopy can be used to probe the energy and dispersion of the elementary low-energy excitations that govern functionality in matter: vibronic, charge, spin and orbital excitations. A key drawback of resonant inelastic X-ray scattering has been the need for high photon densities to compensate for fluorescence yields of less than a per cent for soft X-rays8. Sample damage from the dominant non-radiative decays thus limits the materials to which such techniques can be applied and the spectral resolution that can be obtained. A means of improving the yield is therefore highly desirable. Here we demonstrate stimulated X-ray emission for crystalline silicon at photon densities that are easily achievable with free-electron lasers. The stimulated radiative decay of core excited species at the expense of non-radiative processes reduces sample damage and permits narrow-bandwidth detection in the directed beam of stimulated radiation. We deduce how stimulated X-ray emission can be enhanced by several orders of magnitude to provide, with high yield and reduced sample damage, a superior probe for low-energy excitations and their dispersion in matter. This is the first step to bringing nonlinear X-ray physics in the condensed phase from theory to application. LB - PUB:(DE-HGF)16 UR - <Go to ISI:>//WOS:000324244900034 C6 - pmid:23965622 DO - DOI:10.1038/nature12449 UR - https://bib-pubdb1.desy.de/record/167779 ER -