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arXiv · 1710.08125

Robust formation of topological Hall effect in MnGa/heavy metal bilayers

Abstract

We have investigated the topological Hall effect (THE) in MnGa/Pt and MnGa/Ta bilayers induced by interfacial Dzyaloshinskii-Moriya interaction (DMI). The most evident THE signals have been found based on the MnGa films with small critical DMI energy constant Dc. The large topological portion of the Hall signal from the total Hall signal has been extracted in the whole temperature range from 5 to 300 K. These results open up the exploration of the DMI induced magnetic behavior based on the bulk perpendicular magnetic anisotropy materials for fundamental physics and magnetic storage technologies.

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Kangkang Meng, Xupeng Zhao, Pengfei Liu, Qi Liu, Yong Wu, Jikun Chen, Jun Miao, Xiaoguang Xu, Jianhua Zhao, Yong Jiang. 2018-01-06. Robust formation of topological Hall effect in MnGa/heavy metal bilayers. https://doi.org/10.1103/physrevb.97.060407

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