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arXiv · 1809.04740

Spin Model for Nontrivial Magnetic Orders in the Inverse-Perovskite Antiferromagnets

Masahito Mochizuki·Masaya Kobayashi·Reoya Okabe·Daisuke Yamamoto
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Abstract

Nontrivial magnetic orders in the inverse-perovskite manganese nitrides are theoretically studied by constructing a classical spin model describing the magnetic anisotropy and frustrated exchange interactions inherent in specific crystal and electronic structures of these materials. With a replica-exchange Monte-Carlo technique, a theoretical analysis of this model reproduces the experimentally observed triangular Γ^{5g} and Γ^{4g} spin ordered patterns and the systematic evolution of magnetic orders. Our work solves a 40-year-old problem of nontrivial magnetism for the inverse-perovskite manganese nitrides and provides a firm basis for clarifying the magnetism-driven negative thermal expansion phenomenon discovered in this class of materials.

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Masahito Mochizuki, Masaya Kobayashi, Reoya Okabe, Daisuke Yamamoto. 2018-09-13. Spin Model for Nontrivial Magnetic Orders in the Inverse-Perovskite Antiferromagnets. https://doi.org/10.1103/physrevb.97.060401

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