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arXiv · 2411.01824

Imprinting electrically switchable scalar spin chirality by anisotropic strain in a Kagome antiferromagnet

Abstract

Topological chiral antiferromagnets, such as Mn$_{3}$Sn, are emerging as promising materials for next-generation spintronic devices due to their intrinsic transport properties linked to exotic magnetic configurations. Here, we demonstrate that anisotropic strain in Mn$_{3}$Sn thin films offers a novel approach to manipulate the magnetic ground state, unlocking new functionalities in this material. Anisotropic strain reduces the point group symmetry of the manganese (Mn) Kagome triangles from $C_{3v}$ to $C_{1}$, significantly altering the energy landscape of the magnetic states in Mn$_{3}$Sn. This symmetry reduction enables even a tiny in-plane Dzyaloshinskii-Moriya (DM) interaction to induce canting of the Mn spins out of the Kagome plane. The modified magnetic ground state introduces a finite scalar spin chirality and results in a significant Berry phase in momentum space. Consequently, a large anomalous Hall effect emerges in the Kagome plane at room temperature - an effect that is absent in the bulk material. Moreover, this two-fold degenerate magnetic state enables the creation of multiple-stable, non-volatile anomalous Hall resistance (AHR) memory states. These states are field-stable and can be controlled by thermal assisted current-induced magnetization switching requiring modest current densities and small bias fields, thereby offering a compelling new functionality in Mn$_{3}$Sn for spintronic applications.

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BibTeXRIS

Debjoty Paul, Shivesh Yadav, Shikhar Gupta, Bikash Patra, Nilesh Kulkarni, Debashis Mondal, Kaushal Gavankar, Sourav K. Sahu, Biswarup Satpati, Bahadur Singh, Owen Benton, Shouvik Chatterjee. 2024-11-04. Imprinting electrically switchable scalar spin chirality by anisotropic strain in a Kagome antiferromagnet. https://doi.org/10.1002/advs.202502569

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