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Mesoscopic Kondo screening effect in a single-electron transistor embedded in a metallic ring

Hui Hu·Guang-Ming Zhang·Lu Yu
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Abstract

We study the Kondo screening effect generated by a single-electron transistor or quantum dot embedded in a small metallic ring. When the ring circumference $L$ becomes comparable to the fundamental length scale $ξ_K^0=\hbar \upsilon _F/T_K^0$ associated with the {\it bulk} Kondo tempe the Kondo resonance is strongly affected, depending on the total number of electrons ({\it modulo} 4) and magnetic flux threading the ring. The resulting Kondo-assisted persistent currents are also calculated in both Kondo and mixed valence regimes, and the maximum values are found in the crossover region.

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Hui Hu, Guang-Ming Zhang, Lu Yu. 2001-06-05. Mesoscopic Kondo screening effect in a single-electron transistor embedded in a metallic ring. https://doi.org/10.1103/physrevlett.86.5558

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