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arXiv · 2411.03650

Distinct topological Hall responses in CeCu$_2$-type EuZn$_2$ and EuCd$_2$ films

Yuto Watanabe·Shinichi Nishihaya·Markus Kriener·Ayano Nakamura·Masaki Uchida
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Abstract

Rare earth intermetallic compounds crystallized in AlB$_2$-type and its low-symmetry derivative CeCu$_2$-type structures potentially host diverse frustrated magnetic structures and rich magnetotransport phenomena. We report the film growth of CeCu$_2$-type EuZn$_2$ by molecular beam epitaxy and the observation of topological Hall responses highly contrastive to isostructural EuCd$_2$. While their magnetization curves are rather similar, the topological Hall effect observed in EuZn$_2$ is simpler, with the only one component enhanced at the magnetic transition field. EuZn$_2$ may be a unique system for studying the magnetic domain boundary effect on topological Hall responses among the CeCu$_2$-type rare-earth intermetallic compounds.

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Yuto Watanabe, Shinichi Nishihaya, Markus Kriener, Ayano Nakamura, Masaki Uchida. 2024-11-06. Distinct topological Hall responses in CeCu$_2$-type EuZn$_2$ and EuCd$_2$ films. https://arxiv.org/abs/2411.03650

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