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arXiv · 2203.03569

Texture-induced spin-orbit coupling and Skyrmion-electron bound states in a N\'eel antiferromagnet

Naïmo Davier·Revaz Ramazashvili
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Abstract

We derive effective-mass electron Hamiltonian for a N\'eel antiferromagnet in the presence of a smooth texture of the staggered magnetization. For certain locations of electron band extrema, the texture produces a peculiar and anomalously strong spin-orbit coupling of the scale $\hbar v / L$, with $v$ the Fermi velocity and $L$ the characteristic length scale of the texture. For a Skyrmion texture, this coupling generates electron bound states, whose energy scale is given by the gap $\Delta$ in the electron spectrum. With dopant carriers, such bound states turn the Skyrmion into a charged particle, that can be manipulated by electric field.

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Naïmo Davier, Revaz Ramazashvili. 2022-03-07. Texture-induced spin-orbit coupling and Skyrmion-electron bound states in a N\'eel antiferromagnet. https://doi.org/10.1103/physrevb.107.014406

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