Cotunneling at resonance for the single-electron transistor

TL;DR

This paper investigates cotunneling effects at resonance in single-electron transistors using a novel diagrammatic approach, revealing significant modifications to existing theories and aligning well with experimental data.

Contribution

The authors develop a cut-off free diagrammatic method to analyze cotunneling at resonance, providing more accurate theoretical predictions.

Findings

Significant modifications of previous cotunneling theories at resonance

Good agreement with recent experimental results

No cut-off required in the formulation

Abstract

We study electron transport through a small metallic island in the perturbative regime. Using a recently developed diagrammatic technique, we calculate the occupation of the island as well as the conductance through the transistor in forth order in the tunneling matrix elements, a process referred to as cotunneling. Our formulation does not require the introduction of a cut-off. At resonance we find significant modifications of previous theories and good agreement with recent experiments.