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arXiv · 2106.08622

Topological-chiral magnetic interactions in ultrathin films at surfaces

Soumyajyoti Haldar·Sebastian Meyer·André Kubetzka·Stefan Heinze
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Abstract

We demonstrate that topological-chiral magnetic interactions can play a key role for magnetic ground states in ultrathin films at surfaces. Based on density functional theory we show that significant chiral-chiral interactions occur in hexagonal Mn monolayers due to large topological orbital moments which interact with the emergent magnetic field. Due to the competition with higher-order exchange interactions superposition states of spin spirals such as the 2Q state or a distorted 3Q state arise. Simulations of spin-polarized scanning tunneling microscopy images suggest that the distorted 3Q state could be the magnetic ground state of a Mn monolayer on Re(0001).

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Soumyajyoti Haldar, Sebastian Meyer, André Kubetzka, Stefan Heinze. 2021-06-16. Topological-chiral magnetic interactions in ultrathin films at surfaces. https://doi.org/10.1103/physrevb.104.l180404

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