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Kondo Effect and Persistent Currents in a Mesoscopic Ring: Numerically Exact Results

E. V. Anda·C. Busser·G. Chiappe·M. A. Davidovich
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Abstract

We study the persistent current circulating along a mesoscopic ring with a dot side-coupled to it when threaded by a magnetic field. A cluster including the dot and its vicinity is diagonalized and embedded into the rest of the system. The result is numerically exact. We show that a ring of any size can be in the Kondo regime, although for small sizes it depends upon the magnetic flux. In the Kondo regime, the current can be a smooth or a strongly dependent function of the gate potential according to the structure of occupation of the highest energetic electrons of the system.

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E. V. Anda, C. Busser, G. Chiappe, M. A. Davidovich. 2001-06-08. Kondo Effect and Persistent Currents in a Mesoscopic Ring: Numerically Exact Results. https://doi.org/10.1103/physrevb.66.035307

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