General mechanism for orbital selective phase transitions

Yu Zhong Zhang, Hunpyo Lee, Hai Qing Lin, Chang Qin Wu, Harald Olaf Jeschke, Roser Valentí

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

Based on the analysis of a two-orbital Hubbard model within a mean-field approach, we propose a mechanism for an orbital selective phase transition (OSPT) where coexistence of localized and itinerant electrons can be realized. We show that this OSPT exists both at and near half-filling even in the absence of crystal-field splittings or when bandwidths, orbital degeneracies, and magnetic states are equal for both orbitals, provided the orbitals have different band dispersions. Such conditions should generally be satisfied in many materials. We find that this OSPT is not sensitive to the strength of Hund's rule coupling and that heavy doping favors the collinear antiferromagnetic state over the OSPT. We discuss our results in relation to the iron pnictides.

Original languageEnglish
Article number035123
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume85
Issue number3
DOIs
Publication statusPublished - Jan 26 2012
Externally publishedYes

Fingerprint

Phase transitions
orbitals
Hubbard model
Dispersions
Iron
Doping (additives)
Bandwidth
Crystals
Group 5A compounds
Electrons
crystal field theory
bandwidth
iron
electrons

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Electronic, Optical and Magnetic Materials

Cite this

General mechanism for orbital selective phase transitions. / Zhang, Yu Zhong; Lee, Hunpyo; Lin, Hai Qing; Wu, Chang Qin; Jeschke, Harald Olaf; Valentí, Roser.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 85, No. 3, 035123, 26.01.2012.

Research output: Contribution to journalArticle

Zhang, Yu Zhong ; Lee, Hunpyo ; Lin, Hai Qing ; Wu, Chang Qin ; Jeschke, Harald Olaf ; Valentí, Roser. / General mechanism for orbital selective phase transitions. In: Physical Review B - Condensed Matter and Materials Physics. 2012 ; Vol. 85, No. 3.
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