Strain dependence of bonding and hybridization across the metal-insulator transition of VO2

J. Laverock; L. F. J. Piper; A. R. H. Preston; B. Chen; J. McNulty; K. E. Smith; S. Kittiwatanakul; J. W. Lu; S. A. Wolf; P. -A. Glans; J. -H. Guo

doi:10.1103/physrevb.85.081104

arXiv · 1202.2286

Strain dependence of bonding and hybridization across the metal-insulator transition of VO2

J. Laverock·L. F. J. Piper·A. R. H. Preston·B. Chen·J. McNulty·K. E. Smith·S. Kittiwatanakul·J. W. Lu·S. A. Wolf·P. -A. Glans·J. -H. Guo

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Abstract

Soft x-ray spectroscopy is used to investigate the strain dependence of the metal-insulator transition of VO2. Changes in the strength of the V 3d - O 2p hybridization are observed across the transition, and are linked to the structural distortion. Furthermore, although the V-V dimerization is well-described by dynamical mean-field theory, the V-O hybridization is found to have an unexpectedly strong dependence on strain that is not predicted by band theory, emphasizing the relevance of the O ion to the physics of VO2.

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J. Laverock, L. F. J. Piper, A. R. H. Preston, B. Chen, J. McNulty, K. E. Smith, S. Kittiwatanakul, J. W. Lu, S. A. Wolf, P. -A. Glans, J. -H. Guo. 2012-02-10. Strain dependence of bonding and hybridization across the metal-insulator transition of VO2. https://doi.org/10.1103/physrevb.85.081104

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