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Coulomb blockade and Non-Fermi-liquid behavior in quantum dots

Frithjof B. Anders·Eran Lebanon·Avraham Schiller
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Abstract

The non-Fermi-liquid properties of an ultrasmall quantum dot coupled to a lead and to a quantum box are investigated. Tuning the ratio of the tunneling amplitudes to the lead and box, we find a line of two-channel Kondo fixed points for arbitrary Coulomb repulsion on the dot, governing the transition between two distinct Fermi-liquid regimes. The Fermi liquids are characterized by different values of the conductance. For an asymmetric dot, spin and charge degrees of freedom are entangled: a continuous transition from a spin to a charge two-channel Kondo effect evolves. The crossover temperature to the two-channel Kondo effect is greatly enhanced away from the local-moment regime, making this exotic effect accessible in realistic quantum-dot devices.

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Frithjof B. Anders, Eran Lebanon, Avraham Schiller. 2005-05-23. Coulomb blockade and Non-Fermi-liquid behavior in quantum dots. https://doi.org/10.1103/physrevb.70.201306

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