Ferromagnetism in single-band Hubbard models with a partially flat band

Authors
Mielke, A
Citation
A. Mielke, Ferromagnetism in single-band Hubbard models with a partially flat band, PHYS REV L, 82(21), 1999, pp. 4312-4315
Citations number
20
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
82
Issue
21
Year of publication
1999
Pages
4312 - 4315
Database
ISI
SICI code
0031-9007(19990524)82:21<4312:FISHMW>2.0.ZU;2-K
Abstract
A Hubbard model with a single, partially Aat band has ferromagnetic ground states. It is shown that local stability of ferromagnetism implies its glob al stability in such a model: The model has only ferromagnetic ground state s if there are no single spin-flip ground states. Since a single-band Hubba rd model away from half filling describes a metal, this result may open a r oute to metallic ferromagnetism in single-band Hubbard models. [S0031-9007( 99)09222-4].