Fermi-edge singularity in chiral one-dimensional systems far from equilibrium

TL;DR

This paper investigates how strong coupling and nonequilibrium noise influence the Fermi-edge singularity and tunneling behavior in chiral one-dimensional systems, revealing nonperturbative effects and non-Gaussian noise signatures.

Contribution

It introduces a theoretical framework for understanding nonperturbative backaction effects and noise-induced phenomena in strongly coupled, out-of-equilibrium 1D electronic systems.

Findings

Pronounced non-Gaussian noise component breaks charge symmetry.

Shift and shape change of tunneling resonance due to strong coupling.

Manifestation of orthogonality catastrophe and Fermi-edge singularity.

Abstract

We study the effects of strong coupling of a localized state charge to one-dimensional electronic channels out of equilibrium. While the state of this charge and the coupling strengths determine the scattering phase shifts in the channels, the nonequilibrium partitioning noise induces the tunneling transitions to the localized state. The strong coupling leads to a nonperturbative backaction effect which is manifested in the orthogonality catastrophe and the Fermi-edge singularity in the transition rates. We predict an unusually pronounced manifestation of the non-Gaussian component of noise that breaks the charge symmetry, resulting in a nontrivial shape, and a shift of the position of the tunneling resonance.