English

Orbital-assisted metal-insulator transition in VO$_{2}$

Strongly Correlated Electrons 2007-05-23 v1

Abstract

We found direct experimental evidence for an orbital switching in the V 3d states across the metal-insulator transition in VO2_{2}. We have used soft-x-ray absorption spectroscopy at the V L2,3L_{2,3} edges as a sensitive local probe, and have determined quantitatively the orbital polarizations. These results strongly suggest that, in going from the metallic to the insulating state, the orbital occupation changes in a manner that charge fluctuations and effective band widths are reduced, that the system becomes more 1-dimensional and more susceptible to a Peierls-like transition, and that the required massive orbital switching can only be made if the system is close to a Mott insulating regime.

Keywords

Cite

@article{arxiv.cond-mat/0509368,
  title  = {Orbital-assisted metal-insulator transition in VO$_{2}$},
  author = {M. W. Haverkort and Z. Hu and A. Tanaka and W. Reichelt and S. V. Streltsov and M. A. Korotin and V. I. Anisimov and H. H. Hsieh and H. -J. Lin and C. T. Chen and D. I. Khomskii and L. H. Tjeng},
  journal= {arXiv preprint arXiv:cond-mat/0509368},
  year   = {2007}
}