Magnetic fluctuation and pairing instability controlled by the CoO6 distortion in the sodium cobalt oxide

Masahito Mochizuki, Youichi Yanase, Masao Ogata

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

We study how the CoO6 distortion along the c-axis affects the magnetic properties and superconductivity in the novel Co-oxide superconductor Nax CoO2 · y H2 O by analyzing the multiorbital Hubbard model using the fluctuation-exchange approximation. It is shown that through generating the trigonal crystal field, the distortion pushes the Co eg bands up and consequently gives rise to the hole-pocket Fermi surfaces, which have been predicted in the band calculations. As the distortion increases, the hole pockets are enlarged and the ferromagnetic fluctuation as well as the pairing instability increases, which is in good agreement with recent NQR results.

Original languageEnglish
Pages (from-to)875-877
Number of pages3
JournalPhysica B: Condensed Matter
Volume378-380
Issue numberSPEC. ISS.
DOIs
Publication statusPublished - 2006 May 1
Externally publishedYes

Fingerprint

cobalt oxides
Cobalt
Sodium
sodium
Oxides
Oxide superconductors
Hubbard model
Fermi surface
Superconductivity
Fermi surfaces
crystal field theory
Magnetic properties
superconductivity
magnetic properties
Crystals
oxides
approximation
NaCoO2

Keywords

  • CoO distortion
  • Hole-pocket Fermi surface
  • Multiorbital Hubbard model
  • Na CoO · y H O

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Magnetic fluctuation and pairing instability controlled by the CoO6 distortion in the sodium cobalt oxide. / Mochizuki, Masahito; Yanase, Youichi; Ogata, Masao.

In: Physica B: Condensed Matter, Vol. 378-380, No. SPEC. ISS., 01.05.2006, p. 875-877.

Research output: Contribution to journalArticle

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