title: Spatiotemporal stability of a femtosecond hard-x-ray undulator source studied by control of coherent optical phonons.
abstract: We report on the temporal and spatial stability of the first tunable femtosecond undulator hard-x-ray source for ultrafast diffraction and absorption experiments. The 2.5-1 Angstrom output radiation is driven by an initial 50 fs laser pulse employing the laser-electron slicing technique. By using x-ray diffraction to probe laser-induced coherent optical phonons in bulk bismuth, we estimate an x-ray pulse duration of 140+/-30 fs FWHM with timing drifts below 30 fs rms measured over 5 days. Optical control of coherent lattice motion is demonstrated.
authors.affiliation: Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland. paul.beaud@psi.ch
authors.forename: P
authors.initials: P
authors.lastname: Beaud
authors.forename: S L
authors.initials: SL
authors.lastname: Johnson
authors.forename: A
authors.initials: A
authors.lastname: Streun
authors.forename: R
authors.initials: R
authors.lastname: Abela
authors.forename: D
authors.initials: D
authors.lastname: Abramsohn
authors.forename: D
authors.initials: D
authors.lastname: Grolimund
authors.forename: F
authors.initials: F
authors.lastname: Krasniqi
authors.forename: T
authors.initials: T
authors.lastname: Schmidt
authors.forename: V
authors.initials: V
authors.lastname: Schlott
authors.forename: G
authors.initials: G
authors.lastname: Ingold