Spin-Fluctuation Mechanism of Anomalous Temperature Dependence of Magnetocrystalline Anisotropy in Itinerant Magnets

Authors

I. A. Zhuravlev, University of Nebraska-Lincoln
V. P. Antropov, U.S. Department of Energy, Ames, Iowa
K. D. Belashchenko, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

11-2015

Citation

Physical Review Letters 115, 217201 (2015), pp. 1-5.

doi: 10.1103/PhysRevLett.115.217201

Comments

U.S. Government Work

Abstract

The origins of the anomalous temperature dependence of magnetocrystalline anisotropy in (Fe_1−xCo_x)₂B alloys are elucidated using first-principles calculations within the disordered local moment model. Excellent agreement with experimental data is obtained. The anomalies are associated with the changes in band occupations due to Stoner-like band shifts and with the selective suppression of spin-orbit “hot spots” by thermal spin fluctuations. Under certain conditions, the anisotropy can increase, rather than decrease, with decreasing magnetization due to these peculiar electronic mechanisms, which contrast starkly with those assumed in existing models.