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Spin-charge separation and Kondo effect in an open quantum dot

L. I. Glazman·F. W. J. Hekking·A. I. Larkin
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Abstract

We study a quantum dot connected to the bulk by single-mode junctions at almost perfect conductance. Although the average charge $e\langle N \rangle$ of the dot is not discrete, its spin remains quantized: $s=1/2$ or $s=0$, depending (periodically) on the gate voltage. This drastic difference from the conventional mixed-valence regime stems from the existence of a broad-band, dense spectrum of discrete levels in the dot. In the doublet state, the Kondo effect develops at low temperatures. We find the Kondo temperature $T_K$ and the conductance at $T\lesssim T_K$.

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L. I. Glazman, F. W. J. Hekking, A. I. Larkin. 1999-03-11. Spin-charge separation and Kondo effect in an open quantum dot. https://doi.org/10.1103/physrevlett.83.1830

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