7 research outputs found
Generation of Intense Phase-Stable Femtosecond Hard X-ray Pulse Pairs
Coherent nonlinear spectroscopies and imaging in the X-ray domain provide
direct insight into the coupled motions of electrons and nuclei with resolution
on the electronic length and time scale. The experimental realization of such
techniques will strongly benefit from access to intense, coherent pairs of
femtosecond X-ray pulses. We have observed phase-stable X-ray pulse pairs
containing more thank 3 x 10e7 photons at 5.9 keV (2.1 Angstrom) with about 1
fs duration and 2-5 fs separation. The highly directional pulse pairs are
manifested by interference fringes in the superfluorescent and seeded
stimulated manganese K-alpha emission induced by an X-ray free-electron laser.
The fringes constitute the time-frequency X-ray analogue of the Young
double-slit interference allowing for frequency-domain X-ray measurements with
attosecond time resolution.Comment: 39 pages, 13 figures, to be publishe
Recommended from our members
Seeded stimulated X-ray emission at 5.9 keV.
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
Generation of Intense Phase-Stable Femtosecond Hard X-ray Pulse Pairs
Coherent nonlinear spectroscopies and imaging in the X-ray domain provide direct insight into the coupled motions of electrons and nuclei with resolution on the electronic length and time scale. The experimental realization of such techniques will strongly benefit from access to intense, coherent pairs of femtosecond X-ray pulses. We have observed phase-stable X-ray pulse pairs containing more than 3*107 photons at 5.9 keV (2.1 Å) with ~1 fs duration and 2-5 fs separation. The highly directional pulse pairs are manifested by interference fringes in the superfluorescent and seeded stimulated manganese Kα emission induced by an X-ray free-electron laser. The fringes constitute the time-frequency X-ray analogue of Young’s double-slit interference allowing for frequency-domain X-ray measurements with attosecond time resolution