Novel high-pressure monoclinic metallic phase of v 2 O 3

Academic Article

Abstract

  • Vanadium sesquioxide, V2O3, is a prototypical metal-to-insulator system where, in temperature-dependent studies, the transition always coincides with a corundum-to-monoclinic structural transition. As a function of pressure, V2O3 follows the expected behavior of increased metallicity due to a larger bandwidth for pressures up to 12.5 GPa. Surprisingly, for higher pressures when the structure becomes unstable, the resistance starts to increase. Around 32.5 GPa at 300 K, we observe a novel pressure-induced corundum-to-monoclinic transition between two metallic phases, showing that the structural phase transition can be decoupled from the metal-insulator transition. Using x-ray Raman scattering, we find that screening effects, which are strong in the corundum phase, become weakened at high pressures. Theoretical calculations indicate that this can be related to a decrease in coherent quasiparticle strength, suggesting that the high-pressure phase is likely a critical correlated metal, on the verge of Mott-insulating behavior. © 2014 American Physical Society.
  • Published In

    Digital Object Identifier (doi)

    Author List

  • Ding Y; Chen CC; Zeng Q; Kim HS; Han MJ; Balasubramanian M; Gordon R; Li F; Bai L; Popov D
  • Volume

  • 112
  • Issue

  • 5