TY - JOUR
T1 - Photoemission evidence for a Mott-Hubbard metal-insulator transition in VO2
AU - Eguchi, R.
AU - Taguchi, M.
AU - Matsunami, M.
AU - Horiba, K.
AU - Yamamoto, K.
AU - Ishida, Y.
AU - Chainani, A.
AU - Takata, Y.
AU - Yabashi, M.
AU - Miwa, D.
AU - Nishino, Y.
AU - Tamasaku, K.
AU - Ishikawa, T.
AU - Senba, Y.
AU - Ohashi, H.
AU - Muraoka, Y.
AU - Hiroi, Z.
AU - Shin, S.
PY - 2008/8/18
Y1 - 2008/8/18
N2 - The temperature (T) -dependent metal-insulator transition (MIT) in VO2 is investigated using bulk sensitive hard-x-ray (∼8keV) valence-band, core-level, and V2p-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, V3d spectral weight transfer from the coherent (3 d1 C final) states at Fermi level to the incoherent (3 d0 +3 d1 L final) states, corresponding to the lower Hubbard band, leads to gap formation. The spectral shape changes in V1s and V2p core levels as well as the valence band are nicely reproduced from cluster model calculations, providing electronic structure parameters. Resonant PES finds that the 3 d1 L states resonate across the V2p-3d threshold in addition to the 3 d0 and 3 d1 C states. The results support a Mott-Hubbard transition picture for the first-order MIT in VO2.
AB - The temperature (T) -dependent metal-insulator transition (MIT) in VO2 is investigated using bulk sensitive hard-x-ray (∼8keV) valence-band, core-level, and V2p-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, V3d spectral weight transfer from the coherent (3 d1 C final) states at Fermi level to the incoherent (3 d0 +3 d1 L final) states, corresponding to the lower Hubbard band, leads to gap formation. The spectral shape changes in V1s and V2p core levels as well as the valence band are nicely reproduced from cluster model calculations, providing electronic structure parameters. Resonant PES finds that the 3 d1 L states resonate across the V2p-3d threshold in addition to the 3 d0 and 3 d1 C states. The results support a Mott-Hubbard transition picture for the first-order MIT in VO2.
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U2 - 10.1103/PhysRevB.78.075115
DO - 10.1103/PhysRevB.78.075115
M3 - Article
AN - SCOPUS:50049117268
SN - 1098-0121
VL - 78
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 7
M1 - 075115
ER -