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Coulomb blockade and Quantum Critical Points in Quantum Dots

Frithjof B. Anders·Eran Lebanon·Avraham Schiller
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Abstract

An ultrasmall quantum dot coupled to a lead and to a quantum box (a large quantum dot) is investigated. Tuning the tunneling amplitudes to the lead and box, we find a line of unstable non-Fermi-liquid fixed points as function of the gate potentials of the quantum dots, extending to arbitrary charging energies on the small and large quantum dots. These quantum-critical fixed points possess a finite residual entropy. They govern the cross over from one Fermi-liquid regime to another, characterized by distinct (high and low) conductance values.

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Frithjof B. Anders, Eran Lebanon, Avraham Schiller. 2004-06-14. Coulomb blockade and Quantum Critical Points in Quantum Dots. https://doi.org/10.1016/j.physb.2005.01.427

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