Curie temperatures of diluted magnetic semiconductors calculated from first principles
Institut für Festkörperforschung, Forschungszentrum Jülich D-52425 Jülich, Germany
2 Department of Condensed Matter Physics The Institute of Scientific and Industrial Research (ISIR), Osaka University 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
Accepted: 25 November 2002
Curie temperatures of the diluted magnetic semiconductors , (, ), and are evaluated from first principles. The electronic structure is calculated in the local spin density approximation by using the Korringa-Kohn-Rostoker method combined with the coherent potential approximation to describe the substitutional and spin disorder. From the total energy differences between the ferromagnetic state and the spin-glass state, realistic estimations of Curie temperatures are achieved by using a mapping on the Heisenberg model in the mean-field approximation. Effects of additional carrier doping treatments are also investigated. Very large Curie temperatures are obtained, lying above room temperature for , and . Upon hole doping the Curie temperature of further increases, while shows a plateau behavior.
PACS: 75.50.Pp – Magnetic semiconductors
© EDP Sciences, 2003