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arXiv · 2308.08486

Nontrivial Aharonov-Bohm effect and alternating dispersion of magnons in cone-state ferromagnetic rings

Vera Uzunova·Lukas Körber·Agapi Kavvadia·Gwendolyn Quasebarth·Helmut Schultheiss·Attila Kákay·Boris Ivanov
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Abstract

Soft magnetic dots in the form of thin rings have unique topological properties. They can be in a vortex state with no vortex core. Here, we study the magnon modes of such systems both analytically and numerically. In an external magnetic field, magnetic rings are characterized by easy-cone magnetization and shows a giant splitting of doublets for modes with the opposite value of the azimuthal mode quantum number. The effect of the splitting can be refereed as a magnon analog of the topology-induced Aharonov-Bohm effect. For this we develop an analytical theory to describe the non-monotonic dependence of the mode frequencies on the azimuthal mode number, influenced by the balance between the local exchange and non-local dipole interactions.

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Vera Uzunova, Lukas Körber, Agapi Kavvadia, Gwendolyn Quasebarth, Helmut Schultheiss, Attila Kákay, Boris Ivanov. 2023-08-16. Nontrivial Aharonov-Bohm effect and alternating dispersion of magnons in cone-state ferromagnetic rings. https://doi.org/10.1103/physrevb.108.174445

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