title: Ultrafast melting of a charge-density wave in the Mott insulator 1T-TaS2.
abstract: Femtosecond time-resolved core-level photoemission spectroscopy with a free-electron laser is used to measure the atomic-site specific charge-order dynamics of the charge-density wave in the Mott insulator 1T-TaS2. After strong photoexcitation, a prompt loss of charge order and subsequent fast equilibration dynamics of the electron-lattice system are observed. On the time scale of electron-phonon thermalization, about 1 ps, the system is driven across a phase transition from a long-range charge ordered state to a quasiequilibrium state with domainlike short-range charge and lattice order. The experiment opens the way to study the nonequilibrium dynamics of condensed matter systems with full elemental, chemical, and atomic-site selectivity.
authors.affiliation: Institute for Experimental and Applied Physics, University of Kiel, 24098 Kiel, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Hellmann
authors.forename: M
authors.initials: M
authors.lastname: Beye
authors.forename: C
authors.initials: C
authors.lastname: Sohrt
authors.forename: T
authors.initials: T
authors.lastname: Rohwer
authors.forename: F
authors.initials: F
authors.lastname: Sorgenfrei
authors.forename: H
authors.initials: H
authors.lastname: Redlin
authors.forename: M
authors.initials: M
authors.lastname: Kalläne
authors.forename: M
authors.initials: M
authors.lastname: Marczynski-Bühlow
authors.forename: F
authors.initials: F
authors.lastname: Hennies
authors.forename: M
authors.initials: M
authors.lastname: Bauer
authors.forename: A
authors.initials: A
authors.lastname: Föhlisch
authors.forename: L
authors.initials: L
authors.lastname: Kipp
authors.forename: W
authors.initials: W
authors.lastname: Wurth
authors.forename: K
authors.initials: K
authors.lastname: Rossnagel