Non-Perturbative Aspects of Fano Resonances in Quantum Dots: An Exact Treatment

TL;DR

This paper provides an exact, non-perturbative analysis of Fano resonances in quantum dots with two tunneling paths, revealing Kondo-like physics and matching experimental conductance data.

Contribution

It introduces an integrable generalized Anderson model to exactly solve for Fano resonances in quantum dots, advancing understanding of interference effects.

Findings

Exact zero-temperature conductance matches experiments

Non-perturbative solution captures interference effects

Reveals Kondo-like physics in Fano resonances

Abstract

We consider transport through quantum dots with two tunneling paths. Interference between paths gives rise to Fano resonances exhibiting Kondo-like physics. In studying such quantum dots, we employ a generalized Anderson model which we argue to be integrable. The exact solution is non-perturbative in the tunneling strengths of both paths. By exploiting this integrability, we compute the zero temperature linear response conductance of the dot and so obtain reasonable quantitative agreement with the experimental measurements reported in Gores et al. PRB 62, 2188 (2000).