title: Femtosecond all-optical synchronization of an X-ray free-electron laser.
abstract: Many advanced applications of X-ray free-electron lasers require pulse durations and time resolutions of only a few femtoseconds. To generate these pulses and to apply them in time-resolved experiments, synchronization techniques that can simultaneously lock all independent components, including all accelerator modules and all external optical lasers, to better than the delivered free-electron laser pulse duration, are needed. Here we achieve all-optical synchronization at the soft X-ray free-electron laser FLASH and demonstrate facility-wide timing to better than 30 fs r.m.s. for 90 fs X-ray photon pulses. Crucially, our analysis indicates that the performance of this optical synchronization is limited primarily by the free-electron laser pulse duration, and should naturally scale to the sub-10 femtosecond level with shorter X-ray pulses.
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Schulz
authors.affiliation: 1] Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany [2] Center for Free-electron Laser Science (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany [3] University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Grguraš
authors.affiliation: 1] Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany [2] SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: C
authors.initials: C
authors.lastname: Behrens
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Bromberger
authors.affiliation: School of Physical Sciences and National Center for Plasma Science and Technology (NCPST), Dublin City University, Glasnevin, Dublin 9, Ireland.
authors.forename: J T
authors.initials: JT
authors.lastname: Costello
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: M K
authors.initials: MK
authors.lastname: Czwalinna
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Felber
authors.affiliation: SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Hoffmann
authors.affiliation: European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Ilchen
authors.affiliation: Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany.
authors.forename: H Y
authors.initials: HY
authors.lastname: Liu
authors.affiliation: European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Mazza
authors.affiliation: European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Meyer
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Pfeiffer
authors.affiliation: Department of Microelectronics and Computer Science, Lodz University of Technology, ul. Wólczanska 221/223, 90-924 Łódź, Poland.
authors.forename: P
authors.initials: P
authors.lastname: Prędki
authors.affiliation: University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Schefer
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Schmidt
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Wegner
authors.affiliation: Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Schlarb
authors.affiliation: 1] Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany [2] Center for Free-electron Laser Science (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany [3] University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
authors.forename: A L
authors.initials: AL
authors.lastname: Cavalieri