174 research outputs found
Time-, spin-, and angle-resolved photoemission spectroscopy with a 1-MHz 10.7-eV pulse laser
We describe a setup of time-, spin-, and angle-resolved photoemission
spectroscopy (tr-SARPES) employing a 10.7-eV (=115.6 nm) pulse laser
at 1-MHz repetition rate as a probe photon source. This equipment effectively
combines technologies of a high-power Yb:fiber laser, ultraviolet-driven
harmonic generation in Xe gas, and a SARPES apparatus equipped with
very-low-energy-electron-diffraction (VLEED) spin detectors. A high repetition
rate (1 MHz) of the probe laser allows experiments with the photoemission
space-charge effects significantly reduced, despite a high flux of 10
photons/s on the sample. The relatively high photon energy (10.7 eV) also
brings the capability of observing a wide momentum range that covers the entire
Brillouin zone of many materials while ensuring high momentum resolution. The
experimental setup overcomes a low efficiency of spin-resolved measurements,
which gets even more severe for the pump-probed unoccupied states, and affords
for investigating ultrafast electron and spin dynamics of modern quantum
materials with energy and time resolutions of 25 meV and 360 fs, respectively.Comment: 11 pages, 7 figure
Relation between the reducibility structures and between the master actions in the Witten formulation and the Berkovits formulation of open superstring field theory
Prevalence and risk factors for cardiovascular disease among chronic kidney disease patients: results from the Chinese cohort study of chronic kidney disease (C-STRIDE)
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