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arXiv · 1409.2049

Magnetochiral symmetry breaking in a Möbius ring

Oleksandr V. Pylypovskyi·Volodymyr P. Kravchuk·Denis D. Sheka·Denys Makarov·Oliver G. Schmidt·Yuri Gaididei
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Abstract

We show that the interaction of the magnetic subsystem of a curved magnet with the magnet curvature results in coupling of a topologically nontrivial magnetization pattern and topology of the object. The mechanism of this coupling is explored and illustrated by an example of ferromagnetic Möbius ring, where a topologically induced domain wall appears as a ground state in case of strong easy-normal anisotropy. For the Möbius geometry the curvilinear form of the exchange interaction produces an additional effective Dzyaloshinskii-like term which leads to the coupling of the magnetochirality of the domain wall and chirality of the Möbius ring. Two types of domain walls are found, transversal and longitudinal, which are oriented across and along the Möbius ring, respectively. In both cases the effect of magnetochirality symmetry breaking is established. The dependence of the ground state of the Möbius ring on its geometrical parameters and on the value of the easy-normal anisotropy is explored numerically.

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Oleksandr V. Pylypovskyi, Volodymyr P. Kravchuk, Denis D. Sheka, Denys Makarov, Oliver G. Schmidt, Yuri Gaididei. 2014-10-21. Magnetochiral symmetry breaking in a Möbius ring. https://doi.org/10.1103/physrevlett.114.197204

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