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arXiv · cond-mat/9912399

Mesoscopic Kondo Effect in an Aharonov-Bohm Ring

Kicheon Kang·Sung-Chul Shin
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Abstract

An interacting quantum dot inserted in a mesoscopic ring is investigated. A variational ansatz is employed to describe the ground state of the system in the presence of the Aharonov-Bohm flux. It is shown that, for even number of electrons with the energy level spacing smaller than the Kondo temperature, the persistent current has a value similar to that of a perfect ring with the same radius. On the other hand, for a ring with odd number electrons, the persistent current is found to be strongly suppressed compared to that of an ideal ring, which implies the suppression of the Kondo-resonant transmission. Various aspects of the Kondo-assisted persistent current are discussed.

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BibTeXRIS

Kicheon Kang, Sung-Chul Shin. 2000-11-30. Mesoscopic Kondo Effect in an Aharonov-Bohm Ring. https://doi.org/10.1103/physrevlett.85.5619

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