Temperature-dependent magnetocrystalline anisotropy of rare earth/transition metal permanent magnets from first principles: The light RCo5 (R=Y, La - Gd) intermetallics

Christopher E. Patrick and Julie B. Staunton, Phys. Rev. Materials 3. 101401(R), (2019). – Published 3 October 2019 https://doi.org/10.1103/PhysRevMaterials.3.101401

This paper appears as a highlight in the latest version of Physical Review Materials as an Editor's Suggestion.

Rare earth/transition metal intermetallics remain the subject of much experimental and theoretical research due to their unrivaled performance as permanent magnets. A challenge when using electronic structure calculations to model these materials is accounting for the temperature-induced disorder of individual magnetic moments. Here, the authors combine crystal field theory with density-functional calculations to study the temperature-dependent magnetic anisotropy of the RCo${}_5$ family of permanent magnets. The calculations reproduce the huge room temperature anisotropy of SmCo${}_5$ and the spin reorientation transition temperatures of NdCo${}_5$, and highlight interesting 4$f$ electron correlations in CeCo${}_5$ and PrCo${}_5$. More generally, the developed framework provides a parameter-free approach to modeling rare earth/transition metal magnets at nonzero temperature.