Charge ordered insulator without magnetic order studied by correlator projection method

Kota Hanasaki, Masatoshi Imada

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The Hubbard model with additional intersite interaction 'V' (the extended Hubbard model) is investigated by the correlator projection method (CPM). CPM is a newly developed numerical method that combines the equation-of-motion approach and the dynamical mean-field theory. Using this method, properties of the extended Hubbard Model at quarter filling are discussed with special emphasis on the metal-insulator transition induced by electron-electron correlations. As we increase the interaction, a metal-insulator transition to a charge ordered insulator with antiferromagnetic order occurs at low temperatures, but a metal-insulator transition to a charge ordered insulator without magnetic symmetry breaking occurs at intermediate temperatures. Here, the magnetic order is found to be confined to low temperatures because of the smallness of the exchange coupling J eff. The present results are in sharp contrast to the Hatree-Fock approximation whereas they are in agreement with the experimental results on quarter-filled materials with strong correlations such as organic BEDT-TTF conductors.

Original languageEnglish
Pages (from-to)2769-2782
Number of pages14
JournalJournal of the Physical Society of Japan
Volume74
Issue number10
DOIs
Publication statusPublished - 2005 Oct 1
Externally publishedYes

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correlators
projection
insulators
metals
broken symmetry
equations of motion
electrons
conductors
interactions
approximation
temperature

Keywords

  • Extended Hubbard model
  • Intersite Coulomb interaction
  • Metal-insulator transition

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Charge ordered insulator without magnetic order studied by correlator projection method. / Hanasaki, Kota; Imada, Masatoshi.

In: Journal of the Physical Society of Japan, Vol. 74, No. 10, 01.10.2005, p. 2769-2782.

Research output: Contribution to journalArticle

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