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arXiv · 2005.02170

Study of electronic properties, Magnetization and persistent currents in a mesoscopic ring by controlled curvature

Luís Fernando C. Pereira·Fabiano M. Andrade·Cleverson Filgueiras·Edilberto O. Silva
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Abstract

We study the model of a noninteracting spinless electron gas confined to the two-dimensional localized surface of a cone in the presence of external magnetic fields. The localized region is characterized by an annular radial potential. We write the Schrödinger equation and use the thin-layer quantization procedure to calculate the wavefunctions and the energy spectrum. In such a procedure, it arises a geometry induced potential, which depends on both the mean and the Gaussian curvatures. Nevertheless, since we consider a ring with a mesoscopic size, the effects of the Gaussian curvature on the energy spectrum are negligible. The magnetization and the persistent current are analyzed. In the former, we observed the Aharonov-Bohm (AB) and de Haas-van Alphen (dHvA) types oscillations. In the latter, it is observed only the AB type oscillations. In both cases, the curvature increases the amplitude of the oscillations.

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Luís Fernando C. Pereira, Fabiano M. Andrade, Cleverson Filgueiras, Edilberto O. Silva. 2020-05-03. Study of electronic properties, Magnetization and persistent currents in a mesoscopic ring by controlled curvature. https://doi.org/10.1016/j.physe.2021.114760

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