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arXiv · 2503.01517

Universal whirling magnetic orders in non-Heisenberg Tsai-type quasicrystal approximants

Farid Labib·Kazuhiro Nawa·Yusuke Nambu·Hiroyuki Takakura·Yoichi Ikeda·Kazuhiko Deguchi·Masato Matsuura·Asuka Ishikawa·Ryoichi Kajimoto·Kazuhiko Ikeuchi·Taku J. Sato·Ryuji Tamura
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Abstract

Magnetic orders of non-Heisenberg Tsai-type 1/1 approximant crystals (ACs) in the Au-Ga-Dy system were studied through bulk magnetization, neutron diffraction, and inelastic neutron scattering techniques. The results uncovered noncoplanar, ferromagnetic (FM) and antiferromagnetic (AFM) spin configurations whirling along [111] crystallographic axis, which is analogous to those observed in the Tb- and Ho-contained counterparts. The crystal electric field excitations similar to those in the Tb-based counterpart are also observed indicating the strong Ising-like magnetic anisotropy. These comprehensive experiments and analyses have revealed the existence of a universal mechanism that stabilizes noncoplanar FM and AFM structures in non-Heisenberg Tsai-type ACs, independent of the rare-earth species (Tb, Dy, Ho); FM intra-cluster interactions and strong Ising-like anisotropy.

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Farid Labib, Kazuhiro Nawa, Yusuke Nambu, Hiroyuki Takakura, Yoichi Ikeda, Kazuhiko Deguchi, Masato Matsuura, Asuka Ishikawa, Ryoichi Kajimoto, Kazuhiko Ikeuchi, Taku J. Sato, Ryuji Tamura. 2025-03-03. Universal whirling magnetic orders in non-Heisenberg Tsai-type quasicrystal approximants. https://arxiv.org/abs/2503.01517

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