Disorder and Noncollinear Magnetism in Permanent-Magnet Materials with the ThMn₁₂ Structure

Authors

R. Lorenz, Institut für Theoretische Physik, Technische Universität Wien, Wiedner Hauptstrasse 8-10, A-1040 Wein, Austria
J. Hafner, Institut für Theoretische Physik, Technische Universität Wien, Wiedner Hauptstrasse 8-10, A-1040 Wein, Austria
Sitaram Jaswal, University of NebraskaFollow
David J. Sellmyer, University of Nebraska-LincolnFollow

Date of this Version

May 1995

Comments

Published by American Physical Society. Phys. Rev. Lett. 74, 3688 (1995). http://prl.aps.org. Copyright © 1995 American Physical Society. Permission to use.

Abstract

We report calculations of the noncollinear magnetic structures of YFe_12-xMo_x permanent-magnet materials, using a novel variant of a spin-polarized tight-binding–linear-muffin-tin-orbital technique allowing for local spin-quantization axes on each site and considering spin-orbit coupling. The ternary YFe_12-xMo_x compounds crystallize in the tetragonal ThMn₁₂ structure which can be stabilized only by the partial substitution of Fe by an early transition metal like Mo. We show that the substitutional disorder leads to canted spin structures at low Mo content ( x~1) and to spin-glass-like behavior at higher Mo content (x~3).