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arXiv · 2610.12840

Ground-State Phase Diagram of the Effective Model with Antiferromagnetic Nearest-Neighbor and Ferromagnetic Next-Nearest-Neighbor Interactions in 1/1 Periodic Approximants to Icosahedral Quasicrystals

Shinji Watanabe
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Abstract

By performing complete enumeration of all configurations of magnetic moments, we have determined the ground-state phase diagram of the effective model with antiferromagnetic nearest-neighbor interactions $J_1$ and ferromagnetic next-nearest-neighbor interactions $J_2$ on the 1/1 periodic approximant to icosahedral quasicrystal. Depending on the ratio of $J_2/J_1$ and the magnetic anisotropy arising from the crystalline electric field, various non-collinear ferrimagnetic orders and antiferromagnetic orders are shown to be stabilized, whose magnetic space groups are identified as $R\bar{3}$, $C2'/m'$, $Pm'm'2$ and $I_{\rm P}m'\bar{3}'$. We have revealed the topological as well as magnetic property of each ground state with degeneracy, which is useful to understand experimental observations of magnetic structures and domains in the rare-earth-based 1/1 approximants.

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Shinji Watanabe. 2026-10-09. Ground-State Phase Diagram of the Effective Model with Antiferromagnetic Nearest-Neighbor and Ferromagnetic Next-Nearest-Neighbor Interactions in 1/1 Periodic Approximants to Icosahedral Quasicrystals. https://doi.org/10.7566/jpsj.95.084705

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