Electronic structure properties and BCS superconductivity in β-pyrochlore oxides: KOs2O6

R. Saniz, J. E. Medvedeva, Lin Hui Ye, T. Shishidou, Arthur J Freeman

Research output: Contribution to journalArticle

38 Citations (Scopus)

Abstract

We report a first-principles density-functional calculation of the electronic structure and properties of the recently discovered superconducting β-pyrochlore oxide KOs2O6. We find that the electronic structure near the Fermi energy EF is dominated by strongly hybridized Os 5d and O 2p states. A van Hove singularity very close to Ef leads to a relatively large density of states at EF, and the Fermi surface exhibits strong nesting along several directions. These features could provide the scattering processes leading to the observed anomalous temperature dependence of the resistivity and to the rather large specific-heat mass enhancement we obtain from the calculated density of states and the observed specific-heat coefficient. An estimate of Tc within the framework of the BCS theory of superconductivity taking into account the possible effects of spin fluctuations arising from nesting yields the experimental value.

Original languageEnglish
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume70
Issue number10
DOIs
Publication statusPublished - Sep 2004

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Superconductivity
Oxides
Specific heat
Electronic structure
superconductivity
electronic structure
Spin fluctuations
Fermi surface
oxides
Fermi level
specific heat
Electronic properties
Density functional theory
BCS theory
Scattering
trucks
Fermi surfaces
temperature dependence
electrical resistivity
augmentation

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Electronic structure properties and BCS superconductivity in β-pyrochlore oxides : KOs2O6. / Saniz, R.; Medvedeva, J. E.; Ye, Lin Hui; Shishidou, T.; Freeman, Arthur J.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 70, No. 10, 09.2004.

Research output: Contribution to journalArticle

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