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Current-spin-density functional study of persistent currents in quantum rings

S. Viefers·P. Singha Deo·S. M. Reimann·M. Manninen·M. Koskinen
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Abstract

We present a numerical study of persistent currents in quantum rings using current spin density functional theory (CSDFT). This formalism allows for a systematic study of the joint effects of both spin, interactions and impurities for realistic systems. It is illustrated that CSDFT is suitable for describing the physical effects related to Aharonov-Bohm phases by comparing energy spectra of impurity-free rings to existing exact diagonalization and experimental results. Further, we examine the effects of a symmetry-breaking impurity potential on the density and current characteristics of the system and propose that narrowing the confining potential at fixed impurity potential will suppress the persistent current in a characteristic way.

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S. Viefers, P. Singha Deo, S. M. Reimann, M. Manninen, M. Koskinen. 2000-05-03. Current-spin-density functional study of persistent currents in quantum rings. https://doi.org/10.1103/physrevb.62.10668

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