title: Equilibration dynamics and conductivity of warm dense hydrogen.
abstract: We investigate subpicosecond dynamics of warm dense hydrogen at the XUV free-electron laser facility (FLASH) at DESY (Hamburg). Ultrafast impulsive electron heating is initiated by a ≤ 300-fs short x-ray burst of 92-eV photon energy. A second pulse probes the sample via x-ray scattering at jitter-free variable time delay. We show that the initial molecular structure dissociates within (0.9 ± 0.2) ps, allowing us to infer the energy transfer rate between electrons and ions. We evaluate Saha and Thomas-Fermi ionization models in radiation hydrodynamics simulations, predicting plasma parameters that are subsequently used to calculate the static structure factor. A conductivity model for partially ionized plasma is validated by two-temperature density-functional theory coupled to molecular dynamic simulations and agrees with the experimental data. Our results provide important insights and the needed experimental data on transport properties of dense plasmas.
authors.affiliation: Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena, Germany and SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: U
authors.initials: U
authors.lastname: Zastrau
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Sperling
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Becker
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Bornath
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Bredow
authors.affiliation: Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
authors.forename: T
authors.initials: T
authors.lastname: Döppner
authors.affiliation: Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Dziarzhytski
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Fennel
authors.affiliation: SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: L B
authors.initials: LB
authors.lastname: Fletcher
authors.affiliation: Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena, Germany and Helmholtz-Institut Jena, Fröbelstieg 3, 07743 Jena, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Förster
authors.affiliation: Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
authors.forename: C
authors.initials: C
authors.lastname: Fortmann
authors.affiliation: SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: S H
authors.initials: SH
authors.lastname: Glenzer
authors.affiliation: SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA and Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Göde
authors.affiliation: Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: G
authors.initials: G
authors.lastname: Gregori
authors.affiliation: Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Harmand
authors.affiliation: Institut für Optik und Quantenelektronik, Friedrich-Schiller-Universität, Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Hilbert
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Holst
authors.affiliation: Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany and The Hamburg Centre for Ultrafast Imaging, 22761 Hamburg, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Laarmann
authors.affiliation: SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.
authors.forename: H J
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
authors.forename: T
authors.initials: T
authors.lastname: Ma
authors.affiliation: Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: J P
authors.initials: JP
authors.lastname: Mithen
authors.affiliation: Physikalisches Institut, Westfälische Wilhelms-Universität, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Mitzner
authors.affiliation: Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: C D
authors.initials: CD
authors.lastname: Murphy
authors.affiliation: European XFEL, Albert-Einstein-Ring 19, 22761 Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Nakatsutsumi
authors.affiliation: Extreme Matter Institute, GSI Helmholtzzentrum für Schwerionenforschung, 64291 Darmstadt, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Neumayer
authors.affiliation: Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Przystawik
authors.affiliation: Physikalisches Institut, Westfälische Wilhelms-Universität, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Roling
authors.affiliation: Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Schulz
authors.affiliation: Physikalisches Institut, Westfälische Wilhelms-Universität, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Siemer
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Skruszewicz
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Tiggesbäumker
authors.affiliation: Deutsches Elektronen-Synchrotron, Notkestrasse 85, D-22607 Hamburg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Toleikis
authors.affiliation: European XFEL, Albert-Einstein-Ring 19, 22761 Hamburg, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Tschentscher
authors.affiliation: Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom.
authors.forename: T
authors.initials: T
authors.lastname: White
authors.affiliation: Physikalisches Institut, Westfälische Wilhelms-Universität, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Wöstmann
authors.affiliation: Physikalisches Institut, Westfälische Wilhelms-Universität, Wilhelm-Klemm-Straße 10, 48149 Münster, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Zacharias
authors.affiliation: Institut für Physik, Universität Rostock, D-18051 Rostock, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Redmer
mesh_terms: D004553:Electric Conductivity; D004583:Electrons; D057446:Hydrodynamics; D006859:Hydrogen / Q000737:chemistry*; D007834:Lasers; D056004:Molecular Dynamics Simulation; D011789:Quantum Theory; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D006859:Hydrogen