Full Counting Statistics for a Single-Electron Transistor, Non-equilibrium Effects at Intermediate Conductance

TL;DR

This paper analyzes the current fluctuations in a single-electron transistor with intermediate conductance, revealing how nonequilibrium effects and level broadening influence charge transport statistics.

Contribution

It introduces a novel application of the Schwinger-Keldysh approach with drone fermions to account for parameter renormalization in intermediate conductance regimes.

Findings

Nonequilibrium effects cause lifetime broadening of charge states.

Large current fluctuations are suppressed due to level broadening.

The method provides detailed full counting statistics for the system.

Abstract

We evaluate the current distribution for a single-electron transistor with intermediate strength tunnel conductance. Using the Schwinger-Keldysh approach and the drone (Majorana) fermion representation we account for the renormalization of system parameters. Nonequilibrium effects induce a lifetime broadening of the charge-state levels, which suppress large current fluctuations.