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arXiv · 1904.13008

Whirling spin order in the quasicrystal approximant Au$_{72}$Al$_{14}$Tb$_{14}$

Taku J Sato·Asuka Ishikawa·Akira Sakurai·Masashi Hattori·Maxim Avdeev·Ryuji Tamura
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Abstract

Neutron powder diffraction experiment has been performed on the quasicrystal approximant Au$_{72}$Al$_{14}$Tb$_{14}$, a body-center-cubic crystal of icosahedral spin clusters. The long-range antiferromagnetic order was confirmed at the transition temperature $T_{\rm N} = 10.4$ K. The magnetic structure consists of noncoplanar whirling spins on the icosahedral clusters, arranging antiferroic-manner. A simple icosahedral spin-cluster model with uniaxial anisotropy accounts well the whirling spin order as well as the in-field metamagnetic transition, indicating that the icosahedral symmetry is essential.

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Taku J Sato, Asuka Ishikawa, Akira Sakurai, Masashi Hattori, Maxim Avdeev, Ryuji Tamura. 2019-04-30. Whirling spin order in the quasicrystal approximant Au$_{72}$Al$_{14}$Tb$_{14}$. https://doi.org/10.1103/physrevb.100.054417

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