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arXiv · 1305.1553

Persistent current induced by vacuum fluctuations in a quantum ring

O. V. Kibis·O. Kyriienko·I. A. Shelykh
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Abstract

We study theoretically interaction between electrons in a quantum ring embedded in a microcavity and vacuum fluctuations of electromagnetic field in the cavity. It is shown that the vacuum fluctuations can split electron states of the ring with opposite angular momenta. As a consequence, the ground state of electron system in the quantum ring can be associated to nonzero electric current. Since a ground-state current flows without dissipation, such a quantum ring gets a magnetic moment and can be treated as an artificial spin.

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O. V. Kibis, O. Kyriienko, I. A. Shelykh. 2013-06-29. Persistent current induced by vacuum fluctuations in a quantum ring. https://doi.org/10.1103/physrevb.87.245437

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