학술논문
Seeded stimulated X-ray emission at 5.9 keV.
Document Type
article
Author
Doyle, Margaret D; Halavanau, Aliaksei; Zhang, Yu; Michine, Yurina; Everts, Joshua; Fuller, Franklin; Alonso-Mori, Roberto; Yabashi, Makina; Inoue, IChiro; Osaka, Taito; Yamada, Jumpei; Inubushi, Yuichi; Hara, Toru; Kern, Jan; Yano, Junko; Yachandra, Vittal K; Rohringer, Nina; Yoneda, Hitoki; Kroll, Thomas; Pellegrini, Claudio; Bergmann, Uwe
Source
Optica. 10(4)
Subject
Language
Abstract
X-ray free-electron lasers (XFELs) provide intense pulses that can generate stimulated X-ray emission, a phenomenon that has been observed and studied in materials ranging from neon to copper. Two schemes have been employed: amplified spontaneous emission (ASE) and seeded stimulated emission (SSE), where a second color XFEL pulse provides the seed. Both phenomena are currently explored for coherent X-ray laser sources and spectroscopy. Here, we report measurements of ASE and SSE of the 5.9 keV Mn Kα1 fluorescence line from a 3.9 molar NaMnO4 solution, pumped with 7 femtosecond FWHM XFEL pulses at 6.6 keV. We observed ASE at a pump pulse intensity of 1.7 × 1019 W/cm2, consistent with earlier findings. We observed SSE at dramatically reduced pump pulse intensities down to 1.1 × 1017 W/cm2. These intensities are well within the range of many existing XFEL instruments, which supports the experimental feasibility of SSE as a tool to generate coherent X-ray pulses, spectroscopic studies of transition metal complexes, and other applications.