title: Band-selective measurements of electron dynamics in VO2 using femtosecond near-edge x-ray absorption.
abstract: We report on the first demonstration of femtosecond x-ray absorption spectroscopy, made uniquely possible by the use of broadly tunable bending-magnet radiation from "laser-sliced" electron bunches within a synchrotron storage ring. We measure the femtosecond electronic rearrangements that occur during the photoinduced insulator-metal phase transition in VO2. Symmetry- and element-specific x-ray absorption from V2p and O1s core levels (near 500 eV) separately measures the filling dynamics of differently hybridized V3d-O2p electronic bands near the Fermi level.
authors.affiliation: Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA. a.cavalleri1@physics.ox.ac.uk
authors.forename: A
authors.initials: A
authors.lastname: Cavalleri
authors.forename: M
authors.initials: M
authors.lastname: Rini
authors.forename: H H W
authors.initials: HH
authors.lastname: Chong
authors.forename: S
authors.initials: S
authors.lastname: Fourmaux
authors.forename: T E
authors.initials: TE
authors.lastname: Glover
authors.forename: P A
authors.initials: PA
authors.lastname: Heimann
authors.forename: J C
authors.initials: JC
authors.lastname: Kieffer
authors.forename: R W
authors.initials: RW
authors.lastname: Schoenlein