Coulomb-Modified Fano Resonance in a One-Lead Quantum Dot

TL;DR

This paper explores how Coulomb interactions modify Fano resonances in a quantum dot system, revealing complex lineshapes and strong conductance modulation, supported by a developed theoretical model matching experimental data.

Contribution

It introduces a Coulomb-modified Fano resonance model for a quantum dot coupled to a one-dimensional channel, explaining complex lineshapes and conductance modulation.

Findings

Strong Coulomb response modulates conductance by up to 100 times

Lineshapes with up to four extrema observed in the system

Model shows excellent agreement with experimental results

Abstract

We investigate a tunable Fano interferometer consisting of a quantum dot coupled via tunneling to a one-dimensional channel. In addition to Fano resonance, the channel shows strong Coulomb response to the dot, with a single electron modulating channel conductance by factors of up to 100. Where these effects coexist, lineshapes with up to four extrema are found. A model of Coulomb-modified Fano resonance is developed and gives excellent agreement with experiment.