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arXiv · 1312.3687

Phase diagram of a three-dimensional antiferromagnet with random magnetic anisotropy

Felio A. Perez·Pavel Borisov·Trent A. Johnson·Tudor D. Stanescu·David Lederman·M. R. Fitzsimmons·Adam A. Aczel·Tao Hong
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Abstract

Three-dimensional (3D) antiferromagnets with random magnetic anisotropy (RMA) experimentally studied to date do not have random single-ion anisotropies, but rather have competing two-dimensional and three-dimensional exchange interactions which can obscure the authentic effects of RMA. The magnetic phase diagram Fe$_{x}$Ni$_{1-x}$F$_{2}$ epitaxial thin films with true random single-ion anisotropy was deduced from magnetometry and neutron scattering measurements and analyzed using mean field theory. Regions with uniaxial, oblique and easy plane anisotropies were identified. A RMA-induced glass region was discovered where a Griffiths-like breakdown of long-range spin order occurs.

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Felio A. Perez, Pavel Borisov, Trent A. Johnson, Tudor D. Stanescu, David Lederman, M. R. Fitzsimmons, Adam A. Aczel, Tao Hong. 2013-12-13. Phase diagram of a three-dimensional antiferromagnet with random magnetic anisotropy. https://arxiv.org/abs/1312.3687

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