2006/07/31 by Ritsuko Eguchi, R. Eguchi, M. Taguchi +28 · 1 citation
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Atomic physics #Chemistry #Condensed matter physics #Crystallography #Electron #Fermi level #Ga2O3 and related materials #Gas Sensing Nanomaterials and Sensors #Multiplet #Physics #Quantum mechanics #Spectral line #Transition Metal Oxide Nanomaterials #Valence (chemistry) #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.78.075115
published as Phys. Rev. B 78, 075115 (2008) · 6 pages, 3 figures. to be published in Phys. Rev. B
arxiv created 2008/07/30 · openalex publication_date 2008/08/18 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The temperature (T)-dependent metal-insulator transition (MIT) in VO2 is investigated using bulk sensitive hard-x-ray (\ensuremath∼8 keV) valence-band, core-level, and V 2p\ensuremath-3d resonant photoemission spectroscopies (PESs). The valence-band and core-level spectra are compared with full-multiplet cluster model calculations including a coherent screening channel. Across the MIT, V 3d spectral weight transfer from the coherent (3d1\underseṯC final) states at Fermi level to the incoherent (3d0+3d1\underseṯL final) states, corresponding to the lower Hubbard band, leads to gap formation. The spectral shape changes in V 1s and V 2p core levels as well as the valence band are nicely reproduced from cluster model calculations, providing electronic structure parameters. Resonant PES finds that the 3d1\underseṯL states resonate across the V 2p\ensuremath-3d threshold in addition to the 3d0 and 3d1\underseṯC states. The results support a Mott-Hubbard transition picture for the first-order MIT in VO2.