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Weak Charge Quantization as an Instanton of Interacting sigma-model

Alex Kamenev
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Abstract

Coulomb blockade in a quantum dot attached to a diffusive conductor is considered in the framework of the non-linear sigma-model. It is shown that the weak charge quantization on the dot is associated with instanton configurations of the Q-field in the conductor. The instantons have a finite action and are replica non--symmetric. It is argued that such instantons may play a role in the transition regime to the interacting insulator.

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Alex Kamenev. 2000-07-05. Weak Charge Quantization as an Instanton of Interacting sigma-model. https://doi.org/10.1103/physrevlett.85.4160

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