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Curie temperature and quantum phase transitions in the Hubbard model with binary alloy disorder

Krzysztof Byczuk·Martin Ulmke
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Abstract

Magnetic and electric properties of the Hubbard model with binary alloy disorder are studied within the dynamical mean--field theory. A paramagnet--ferromagnet phase transition and a Mott--Hubbard metal--insulator transition are observed upon varying the alloy concentration. A disorder induced enhancement of the Curie temperature is demonstrated and explained by the effects of band splitting and subband filling. Different quantum phase transitions driven by changes of the alloy concentration are identified.

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Krzysztof Byczuk, Martin Ulmke. 2004-11-06. Curie temperature and quantum phase transitions in the Hubbard model with binary alloy disorder. https://doi.org/10.1140/epjb%2Fe2005-00216-2

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