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A New Quantum Phase Transition in the Coupled Quantum Dots System

Natan Andrei·Gergely T. Zimanyi·Gerd Schoen
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Abstract

We study two quantum dots in the limit of strong dot-lead coupling and weak dot-dot tunneling. The model maps on Ising-coupled Kondo impurities. We argue that a new quantum critical fixed point exists at an intermediate value of the mutual capacitance, supporting non-Fermi liquid behaviour. We construct the total conductance across the double dot structure. It exhibits a strongly peaked behaviour as a function of the mutual capacitance, gate voltage, and temperature.

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Natan Andrei, Gergely T. Zimanyi, Gerd Schoen. 1997-11-11. A New Quantum Phase Transition in the Coupled Quantum Dots System. https://arxiv.org/abs/cond-mat/9711098

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