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Conduction through a quantum dot near a singlet-triplet transition

M. Pustilnik·L. I. Glazman
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Abstract

Kondo effect in the vicinity of a singlet-triplet transition in a vertical quantum dot is considered. This system is shown to map onto a special version of the two-impurity Kondo model. At any value of the control parameter, the system has a Fermi-liquid ground state. Explicit expressions for the linear conductance as a function of the control parameter and temperature $T$ are obtained. At T=0, the conductance reaches the unitary limit $\sim 4e^2/h$ at the triplet side of the transition, and decreases with the increasing distance to the transition at the singlet side. At finite temperature, the conductance exhibits a peak near the transition point.

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M. Pustilnik, L. I. Glazman. 2000-09-07. Conduction through a quantum dot near a singlet-triplet transition. https://doi.org/10.1103/physrevlett.85.2993

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