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arXiv · 2012.04390

Instantons in the out-of-equilibrium Coulomb blockade

A. S. Dotdaev·Ya. I. Rodionov·K. S. Tikhonov
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Abstract

Physical properties of single-electron devices in the week Coulomb blockade regime are significantly dependent on non-perturbative effects. They arise as instanton solutions of equations of motion for the corresponding Ambegaokar-Eckern-Schoen action. In equilibrium those solutions are known as Korshunov instantons. In this paper we study non-equilibrium Ambegaokar-Eckern- Schoen action using Keldysh technique. We found instantons for the most general stationary out-of equilibrium state. We also found that action saddle-point value assumes a universal value irrespective of the stationary non-equilibrium state.

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A. S. Dotdaev, Ya. I. Rodionov, K. S. Tikhonov. 2020-12-08. Instantons in the out-of-equilibrium Coulomb blockade. https://doi.org/10.1016/j.physleta.2021.127736

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