Effects of Orbital Degeneracy and Electron Correlation on Charge Dynamics in Perovskite Manganese Oxides

Hiroki Nakano, Yukitoshi Motome, Masatoshi Imada

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Taking the orbital degeneracy of eg conduction bands and the Coulomb interaction into account in a double-exchange model, we investigate the charge dynamics of perovskite Mn oxides by the Lanczös diagonalization method. In the metallic phase near the Mott insulator, it is found that the optical conductivity for a spin-polarized two-dimensional system exhibits a weight transfer to a broad and incoherent structure within the lower-Hubbard band together with a suppressed Drude weight. It reproduces a qualitative feature of the experimental results. As an orbital effect, we find that an anomalous charge correlation at quarter filling suppresses the coherent charge dynamics and signals precursor to the charge ordering.

Original languageEnglish
Pages (from-to)2178-2181
Number of pages4
JournalJournal of the Physical Society of Japan
Volume68
Issue number7
DOIs
Publication statusPublished - 1999 Jan 1
Externally publishedYes

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manganese oxides
orbitals
conduction bands
electrons
insulators
conductivity
oxides
interactions

Keywords

  • Charge ordering
  • Coulumb interaction
  • Double-exchange model
  • Drude weight
  • Exact diagonalization
  • Ferromagnetic metal
  • Incoherent charge dynamics
  • Metal-insulator transition
  • Optical conductivity
  • Orbital degeneracy
  • Perovskite manganites

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Effects of Orbital Degeneracy and Electron Correlation on Charge Dynamics in Perovskite Manganese Oxides. / Nakano, Hiroki; Motome, Yukitoshi; Imada, Masatoshi.

In: Journal of the Physical Society of Japan, Vol. 68, No. 7, 01.01.1999, p. 2178-2181.

Research output: Contribution to journalArticle

Nakano, Hiroki ; Motome, Yukitoshi ; Imada, Masatoshi. / Effects of Orbital Degeneracy and Electron Correlation on Charge Dynamics in Perovskite Manganese Oxides. In: Journal of the Physical Society of Japan. 1999 ; Vol. 68, No. 7. pp. 2178-2181.
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