title: Effects of low-energy excitations on spectral properties at higher binding energy: the metal-insulator transition of VO(2).
abstract: The effects of electron interaction on spectral properties can be understood in terms of coupling between excitations. In transition-metal oxides, the spectral function close to the Fermi level and low-energy excitations between d states have attracted particular attention. In this work we focus on photoemission spectra of vanadium dioxide over a wide (10 eV) range of binding energies. We show that there are clear signatures of the metal-insulator transition over the whole range due to a cross coupling of the delocalized s and p states with low-energy excitations between the localized d states. This coupling can be understood by advanced calculations based on many-body perturbation theory in the GW approximation. We also advocate the fact that tuning the photon energy up to the hard-x-ray range can help to distinguish fingerprints of correlation from pure band-structure effects.
authors.affiliation: Laboratoire des Solides Irradiés, CNRS UMR 7642, CEA-DSM-IRAMIS, École Polytechnique, Université Paris-Saclay, F-91128 Palaiseau, France.|European Theoretical Spectroscopy Facility (ETSF).|Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette, France.
authors.forename: Matteo
authors.initials: M
authors.lastname: Gatti
authors.affiliation: Istituto Officina dei Materiali (IOM)-CNR, Laboratorio TASC, in Area Science Park, S.S.14, Km 163.5, I-34149 Trieste, Italy.
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Panaccione
authors.affiliation: Laboratoire des Solides Irradiés, CNRS UMR 7642, CEA-DSM-IRAMIS, École Polytechnique, Université Paris-Saclay, F-91128 Palaiseau, France.|European Theoretical Spectroscopy Facility (ETSF).
authors.forename: Lucia
authors.initials: L
authors.lastname: Reining