Journal article

Pressure-driven insulator-metal transition in cubic phase UO 2

  • Huang, Li Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang, China
  • Wang, Yilin Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, USA
  • Werner, Philipp Department of Physics, University of Fribourg, Switzerland
    21.11.2017
Published in:
  • EPL (Europhysics Letters). - 2017, vol. 119, no. 5, p. 57007
English Understanding the electronic properties of actinide oxides under pressure poses a great challenge for experimental and theoretical studies. Here, we investigate the electronic structure of cubic phase uranium dioxide at different volumes using a combination of density functional theory and dynamical mean-field theory. The ab initio calculations predict an orbital-selective insulator-metal transition at a moderate pressure of ∼45 GPa. At this pressure the uranium's 5 f 5/2 state becomes metallic, while the 5 f 7/2 state remains insulating up to about 60 GPa. In the metallic state, we observe a rapid decrease of the 5 f occupation and total angular momentum with pressure. Simultaneously, the so-called “Zhang-Rice state”, which is of predominantly 5 f 5/2 character, quickly disappears after the transition into the metallic phase.
Faculty
Faculté des sciences et de médecine
Department
Département de Physique
Language
  • English
Classification
Physics
License
License undefined
Identifiers
Persistent URL
https://folia.unifr.ch/unifr/documents/306311
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