Fermi-edge singularity and related interaction induced phenomena in multilevel quantum dots

TL;DR

This paper investigates non-perturbative interaction effects in tunnelling between chiral quantum Hall edge channels and multilevel quantum dots, revealing universal behaviors and the impact of plasmon dispersion and neutral modes.

Contribution

It introduces an alternative bosonization-based approach to analyze Fermi-edge singularity and plasmon-assisted tunnelling in multilevel quantum dots, including effects of spectrum dispersion and neutral modes.

Findings

Universal tunnelling rate behavior in certain regimes

Interaction-induced level broadening effects analyzed

Impact of plasmon dispersion and neutral modes on tunnelling

Abstract

We study the manifestation of the non-perturbative effects of interaction in sequential tunnelling between a quasi-one dimensional system of chiral quantum Hall edge channels and a multilevel quantum dot (QD). We use the formal scattering theory approach to the bosonization technique to present an alternative derivation of the Fermi-edge singularity (FES) effect and demonstrate the origin of its universality. This approach allows us to address, within the same framework, plasmon assisted sequential tunnelling to relatively large dots and investigate the interaction induced level broadening. The results are generalised by taking into account the dispersion in the spectrum of plasmons in the QD. We then discuss their modification in the presence of neutral modes, which can be realised either in a QD with two chiral strongly interacting edge channels or in a three dimensional QD in the Coulomb blockade regime. In the former case a universal behaviour of the tunnelling rate is discovered.