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arXiv · 2111.10505

Giant Dzyaloshinskii-Moriya interaction and ratchet motion of bimeronic excitations in two-dimensional magnets

Shunhong Zhang·Xiaoyin Li·Huisheng Zhang·Ping Cui·Xiaohong Xu·Zhenyu Zhang
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Abstract

Topological magnetic excitations rooted in Dzyaloshinskii-Moriya interaction (DMI) are promising information carriers for next-generation memory and spintronic devices. The recently discovered two-dimensional (2D) magnets provide fertile new platforms for revealing rich physical phenomena with atomic-scale precision, as exemplified by the enhanced DMI associated with an effective electric field that breaks the inversion symmetry. Here we use first-principles calculations to establish a conceptually difierent compositional engineering approach to induce giant DMI in a representative CrMnI$_6$ 2D magnet, and the underlying mechanism is rooted in the spontaneous inversion symmetry breaking in the bipartite system. Using atomistic magnetics simulations, we further reveal that bimeronic excitations can emerge upon cooling a spin random state or perturbing a ferromagnetic state. Strikingly, the bimeron can exhibit unidirectional soliton-like propagation, and such a ratchet phenomenon is highly desirable for racetrack memories. These findings may prove instrumental in developing novel devices for quantum information based on 2D magnets.

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Shunhong Zhang, Xiaoyin Li, Huisheng Zhang, Ping Cui, Xiaohong Xu, Zhenyu Zhang. 2021-11-20. Giant Dzyaloshinskii-Moriya interaction and ratchet motion of bimeronic excitations in two-dimensional magnets. https://arxiv.org/abs/2111.10505

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