Topological Hall effect in bulk ferromagnet Cr$_2$Te$_3$ embedded with black-phosphorus-like bismuth nanosheets

Liang Zhou; Junshu Chen; Xiaobin Chen; Bin Xi; Yang Qiu; Junwei Zhang; Linjing Wang; Runnan Zhang; Bicong Ye; Pingbo Chen; Xixiang Zhang; Guoping Guo; Dapeng Yu; Jia-Wei Mei; Fei Ye; Gan Wang; Hongtao He

arXiv · 1903.06486

Topological Hall effect in bulk ferromagnet Cr$_2$Te$_3$ embedded with black-phosphorus-like bismuth nanosheets

Liang Zhou·Junshu Chen·Xiaobin Chen·Bin Xi·Yang Qiu·Junwei Zhang·Linjing Wang·Runnan Zhang·Bicong Ye·Pingbo Chen·Xixiang Zhang·Guoping Guo·Dapeng Yu·Jia-Wei Mei·Fei Ye·Gan Wang·Hongtao He

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Abstract

We implement the molecular beam epitaxy method to embed the black-phosphorus-like bismuth nanosheets into the bulk ferromagnet Cr$_2$Te$_3$. As a typical surfactant, bismuth lowers the surface tensions and mediates the layer-by-layer growth of Cr$_2$Te$_3$. Meanwhile, the bismuth atoms precipitate into black-phosphorus-like nanosheets with the lateral size of several tens of nanometers. In Cr$_2$Te$_3$ embedded with Bi-nanosheets, we observe simultaneously a large topological Hall effect together with the magnetic susceptibility plateau and magnetoresistivity anomaly. As a control experiment, none of these signals is observed in the pristine Cr$_2$Te$_3$ samples. Therefore, the Bi-nanosheets serve as seeds of topological Hall effect induced by non-coplanar magnetic textures planted into Cr$_2$Te$_3$. Our experiments demonstrate a new method to generates a large topological Hall effect by planting strong spin-orbit couplings into the traditional ferromagnet, which may have potential applications in spintronics.

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Liang Zhou, Junshu Chen, Xiaobin Chen, Bin Xi, Yang Qiu, Junwei Zhang, Linjing Wang, Runnan Zhang, Bicong Ye, Pingbo Chen, Xixiang Zhang, Guoping Guo, Dapeng Yu, Jia-Wei Mei, Fei Ye, Gan Wang, Hongtao He. 2019-03-15. Topological Hall effect in bulk ferromagnet Cr$_2$Te$_3$ embedded with black-phosphorus-like bismuth nanosheets. https://arxiv.org/abs/1903.06486

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