Coulomb Blockade and Super Universality of the Theta-Angle

TL;DR

This paper develops a quantum theory of the single electron transistor revealing a new quantized observable linked to noise, demonstrating super universal topological features akin to the quantum Hall effect.

Contribution

It introduces a previously unrecognized quantized observable q' in Coulomb blockade systems, related to noise, and unifies topological features across different quantum phenomena.

Findings

Identification of a new quantized observable q'

Development of a unifying scaling diagram in q'-g' plane

Demonstration of super universal topological features similar to quantum Hall effect

Abstract

Based on the Ambegaokar-Eckern-Schon approach to the Coulomb blockade we develop a complete quantum theory of the single electron transistor. We identify a previously unrecognized physical observable q^\prime in the problem that, unlike the usual average charge (Q) on the island, is robustly quantized for any finite value of the tunneling conductance as the temperature goes to absolute zero. This novel quantity is fundamentally related to the non-symmetrized noise of the system. We present a unifying scaling diagram in the q^\prime - g^\prime plane where g^\prime denotes the conductance of the system. The results display all the super universal topological features of the theta-angle concept that previously arose in the theory of the quantum Hall effect.