Bulk- and Surface-Sensitive High-Resolution Photoemission Study of Two Mott-Hubbard Systems : SrVO3 and CaVO3

Eguchi Ritsuko

Kiss Takayuki

Tsuda Shunsuke

Shimojima Takahiro

Mizokami Tomohiro

Yokoya Takayoshi

Chainani Ashish

Shin Shik

Inoue Isao H.

Togashi Tadashi

Watanabe Shuntaro

Zhang C. Q.

Chen C. T.

Arita Masashi

Shimada Kenya

Namatame Hirofumi

Taniguchi Masaki

Physical Review Letters

We study the electronic structure of Mott-Hubbard systems SrVO3 and CaVO3 with bulk and surface-sensitive high-resolution photoemission spectroscopy, using a vacuum ultraviolet laser, synchrotron radiation, and a discharge lamp (hν=7–21 eV). A systematic suppression of the density of states (DOS) within ~0.2 eV of the Fermi level (EF) is found on decreasing photon energy, i.e., on increasing bulk sensitivity. The coherent band in SrVO3 and CaVO3 is shown to consist of surface and bulk-derived features, separated in energy. The stronger distortion on surface of CaVO3 compared to SrVO3 leads to a higher surface metallicity in the coherent DOS at EF, consistent with recent theory.

photoemission

binding energy

photoelectron spectra

strontium compounds

calcium compounds

electronic density of states

Fermi level

strongly correlated electron systems

eng

American Physical Society

Copyright (c) 2006 The American Physical Society.

[ISSN] 0031-9007

[DOI] 10.1103/PhysRevLett.96.076402

[NCID] AA00773679

[DOI] http://dx.doi.org/10.1103/PhysRevLett.96.076402