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arXiv · 1911.12952

Magnetic orders induced by RKKY interaction in Tsai-type quasicrystalline approximant Au-Al-Gd

Haruka Miyazaki·Takanori Sugimoto·Katsuhiro Morita·Takami Tohyama
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Abstract

Recent experimental study on Tsai-type quasicrystalline approximant Au-Al-Gd has revealed the presence of magnetic orders and phase transitions with changing the Au/Al concentration. Motivated by the experiment, we theoretically investigate whether a successive change of magnetic orders occurs in a minimal magnetic model including the RKKY interaction only. We find that the model induces multifarious magnetic orders depending on the Fermi wavenumber and gives a good starting point for understanding the experimental observation. In addition, we predict the presence of an undiscovered novel magnetic order called cuboc order at large Fermi wavenumber region.

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Haruka Miyazaki, Takanori Sugimoto, Katsuhiro Morita, Takami Tohyama. 2019-11-29. Magnetic orders induced by RKKY interaction in Tsai-type quasicrystalline approximant Au-Al-Gd. https://doi.org/10.1103/physrevmaterials.4.024417

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