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arXiv · 0712.2635

Neutron scattering study on spin correlations and fluctuations in the transition-metal-based magnetic quasicrystal Zn-Fe-Sc

Taku J Sato·Shiro Kashimoto·Chihiro Masuda·Takahiro Onimaru·Isao Nakanowatari·Kazuki Iida·Rei Morinaga·Tsutomu Ishimasa
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Abstract

Spin correlations and fluctuations in the 3d-transition-metal-based icosahedral quasicrystal Zn-Fe-Sc have been investigated by neutron scattering using polycrystalline samples. Magnetic diffuse scattering has been observed in the elastic experiment at low temperatures, indicating development of static short-range-spin correlations. In addition, the inelastic scattering experiment detects a $Q$-independent quasielastic signal ascribed to single-site relaxational spin fluctuations. Above the macroscopic freezing temperature $T_{\rm f} \simeq 7$ K, the spin relaxation rate shows Arrhenius-type behavior, indicating thermally activated relaxation process. In contrast, the relaxation rate remains finite even at the lowest temperature, suggesting a certain quantum origin for the spin fluctuations below $T_{\rm f}$.

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Taku J Sato, Shiro Kashimoto, Chihiro Masuda, Takahiro Onimaru, Isao Nakanowatari, Kazuki Iida, Rei Morinaga, Tsutomu Ishimasa. 2007-12-17. Neutron scattering study on spin correlations and fluctuations in the transition-metal-based magnetic quasicrystal Zn-Fe-Sc. https://doi.org/10.1103/physrevb.77.014437

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