Relaxation and revival of quasiparticles injected in an interacting quantum Hall liquid

R H Rodriguez,A Cavanna,P Roulleau,F D Parmentier,D Mailly,U Gennser,D Ferraro,F Portier,P Roche,M Sassetti

doi:10.1038/s41467-020-16331-4

Abstract

The one-dimensional, chiral edge channels of the quantum Hall effect are a promising platform in which to implement electron quantum optics experiments; however, Coulomb interactions between edge channels are a major source of decoherence and energy relaxation. It is therefore of large interest to understand the range and limitations of the simple quantum electron optics picture. Here we confirm experimentally for the first time the predicted relaxation and revival of electrons injected at finite energy into an edge channel. The observed decay of the injected electrons is reproduced theoretically within a Tomonaga-Luttinger liquid framework, including an important dissipation towards external degrees of freedom. This gives us a quantitative empirical understanding of the strength of the interaction and the dissipation.

Highlights

The one-dimensional, chiral edge channels of the quantum Hall effect are a promising platform in which to implement electron quantum optics experiments; Coulomb interactions between edge channels are a major source of decoherence and energy relaxation
The injected quasiparticles propagate over a finite length L, after which we perform a spectroscopy of the energy distribution function f(E) of the quasiparticles using a second downstream quantum dot (QD) as energy filter
It is worth noting that other experimental techniques can be used to probe the energy distribution function, by measuring shot noise[30], or by performing a quantum tomography of the excitation injected in the EC31–34

Summary

Results

The injected quasiparticles propagate over a finite length L, after which we perform a spectroscopy of the energy distribution function f(E) of the quasiparticles using a second downstream QD as energy filter This spectroscopy technique combined with a quantum point contact to generate excitations was previously used in refs. It is worth noting that other experimental techniques can be used to probe the energy distribution function, by measuring shot noise[30], or by performing a quantum tomography of the excitation injected in the EC31–34. The latter is known for being among the most challenging experiments undertaken so far in electron quantum optics

P2 VS eVD

Discussion

Methods