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arXiv · 2207.12556

Modification of Landau levels in a two-dimensional ring due to rotation effects and edge states

Abstract

We investigate the properties of a two-dimensional quantum ring under rotating and external magnetic field effects. We initially analyse the Landau levels and inertial effects on them. Among the results obtained, we emphasize that the rotation lifted the degeneracy of Landau levels. When electrons are confined in a two-dimensional ring, which is modeled by a hard wall potential, the eigenstates are described by Landau states as long as the eigenstates are not too close to the edges of the ring. On the other hand, near the edges of the ring, the energies increase monotonically. These states are known as edge states. Edge states have an important effect on the physical properties of the ring. Thus, we analyze the Fermi energy and magnetization. In the specific case of magnetization, we consider two approaches. In the first, we obtain an analytical result for magnetization but without considering rotation. Numerical results showed the de Haas-Van Alphen (dHvA) oscillations. In the second, we consider rotating effects. In addition to the dHvA oscillations, we also verify the Aharonov-Bohm-type (AB) oscillations, which are associated with the presence of edge states. We discuss the effects of rotation on the results and find that rotation is responsible for inducing Aharonov-Bohm-type oscillations.

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Luís Fernando C. Pereira, Edilberto O. Silva. 2022-07-25. Modification of Landau levels in a two-dimensional ring due to rotation effects and edge states. https://doi.org/10.1002/andp.202200371

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