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arXiv · 1602.08933

Tailoring Magnetic Frustration in Strained Epitaxial FeRh Films

Abstract

We report on a strain-induced martensitic transformation, accompanied by a suppression of magnetic order in epitaxial films of chemically disordered FeRh. X-ray diffraction, transmission electron microscopy and electronic structure calculations reveal that the lowering of symmetry (from cubic to tetragonal) imposed by the epitaxial relation leads to a further, unexpected, tetragonal-to-orthorhombic transition, triggered by a band-Jahn-Teller-type lattice instability. The collapse of magnetic order is a direct consequence of this structural change, which upsets the subtle balance between ferromagnetic nearest-neighbor interactions arising from Fe-Rh hybridization and frustrated antiferromagnetic coupling among localized Fe moments at larger distances.

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Ralf Witte, Robert Kruk, Markus E. Gruner, Richard A. Brand, Di Wang, Sabine Schlabach, Andre Beck, Virgil Provenzano, Rossitza Pentcheva, Heiko Wende, Horst Hahn. 2016-02-29. Tailoring Magnetic Frustration in Strained Epitaxial FeRh Films. https://doi.org/10.1103/physrevb.93.104416

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