Transfer of spectral weight and symmetry across the metal-insulator transition in VO2

• We present a detailed study of the valence and conduction bands of VO2 across the metal-insulator transition using bulk-sensitive photoelectron and O K x-ray absorption spectroscopies. We observe a giant transfer of spectral weight with distinct features that require an explanation which goes beyond the Peierls transition model as well as the standard single-band Hubbard model. Analysis of the symmetry and energies of the bands reveals the decisive role of the V 3d orbital degrees of freedom. Comparison to recent realistic many body calculations shows that much of the k dependence of the self-energy correction can be cast within a dimer model.

Nyckelord

x-ray photoelectron

electronic-structure

phase-transitions

mott-hubbard

band theory

photoemission

oxides

v2o3

temperature

absorption

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)