Orbital degeneracy as a source of frustration in LiNiO2

F. Vernay, K. Penc, P. Fazekas, F. Mila

Research output: Contribution to journalArticle

72 Citations (Scopus)

Abstract

Motivated by the absence of cooperative Jahn-Teller effect and of magnetic ordering in LiNiO2, a layered oxide with triangular planes, we study a general spin-orbital model on the triangular lattice. A mean-field approach reveals the presence of several singlet phases between the SU(4) symmetric point and a ferromagnetic phase, a conclusion supported by exact diagonalizations of finite clusters. We argue that one of the phases, characterized by a large number of low-lying singlets associated to dimer coverings of the triangular lattice, could explain the properties of LiNiO2, while a ferro-orbital phase that lies nearby in parameter space leads to a new prediction for the magnetic properties of NaNiO2.

Original languageEnglish
Article number014428
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume70
Issue number1
DOIs
Publication statusPublished - Jul 2004

Fingerprint

Jahn-Teller effect
frustration
Dimers
Oxides
Magnetization
Magnetic properties
orbitals
coverings
dimers
magnetic properties
oxides
predictions

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Orbital degeneracy as a source of frustration in LiNiO2. / Vernay, F.; Penc, K.; Fazekas, P.; Mila, F.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 70, No. 1, 014428, 07.2004.

Research output: Contribution to journalArticle

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