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THz pulse doubler at FLASH: double pulses for pump-probe experiments at X-ray FELs.

ABSTRACT: FLASH, the X-ray free-electron laser in Hamburg, Germany, employs a narrowband high-field accelerator THz source for unique THz pump X-ray probe experiments. However, the large difference in optical paths of the THz and X-ray beamlines prevents utilization of the machine's full potential (e.g. extreme pulse energies in the soft X-ray range). To solve this issue, lasing of double electron bunches, separated by 28 periods of the driving radiofrequency (at 1.3?GHz), timed for the temporal overlap of THz and X-ray pulses at the experimental station has been employed. In order to optimize conditions for a typical THz pump X-ray probe experiment, X-ray lasing of the first bunch to one-sixth of that of the second has been suppressed. Finally, synchronization of THz radiation pulses was measured to be ?20?fs (r.m.s.), and a solution for monitoring the arrival time for achieving higher temporal resolution is presented.

SUBMITTER: Zapolnova E

PROVIDER: S-EPMC5741119 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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THz pulse doubler at FLASH: double pulses for pump-probe experiments at X-ray FELs.

Zapolnova Ekaterina E Golz Torsten T Pan Rui R Klose Karsten K Schreiber Siegfried S Stojanovic Nikola N

Journal of synchrotron radiation 20180101 Pt 1

FLASH, the X-ray free-electron laser in Hamburg, Germany, employs a narrowband high-field accelerator THz source for unique THz pump X-ray probe experiments. However, the large difference in optical paths of the THz and X-ray beamlines prevents utilization of the machine's full potential (e.g. extreme pulse energies in the soft X-ray range). To solve this issue, lasing of double electron bunches, separated by 28 periods of the driving radiofrequency (at 1.3 GHz), timed for the temporal overlap o ...[more]

PMID: 29271749

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