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arXiv · 1106.3730

Anomalous slow dynamics in the metallic helimagnet Gd_{1-x}Y_{x}

Teruo Yamazaki·Yohikazu Tabata·Takeshi Waki·Hiroyuki Nakamura
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Abstract

Ac-suseptibility measurements were performed in the metallic helimagnet Gd_{1-x}Y_{x} alloy. A remarkable increase of the imaginary part of the ac-suseptibility was observed in the temperature range of the helimagnetic phase. Moreover, a strong nonlinearity of the magnetization was observed at paramagnetic-helimagnetic transition temperature T_{N}. On the other hand, These anomalous behavior were not observed in similar rare-earth helimagnets Ho and Ho_{1-x}Y_{x}. It strongly suggests that the weak magnetic anisotropy of the Gd-moments is responsible for the anomalous slow dynamics in the helimagnetic phase and for the strong nonlinearity of the magnetization at T_{N}. The slow dynamics may result from a chiral-domain motion, or a long-time variation of the period of the helimagnetic structure.

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Teruo Yamazaki, Yohikazu Tabata, Takeshi Waki, Hiroyuki Nakamura. 2011-06-19. Anomalous slow dynamics in the metallic helimagnet Gd_{1-x}Y_{x}. https://doi.org/10.1088/1742-6596%2F320%2F1%2F012068

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