Taming electronic decoherence in 1D chiral ballistic quantum conductors

TL;DR

This paper investigates intrinsic and extrinsic electron decoherence in 1D chiral quantum conductors, highlighting material properties and sample design strategies to minimize decoherence for quantum information applications.

Contribution

It provides a detailed analysis of how material choice and sample geometry influence electron decoherence, proposing methods to suppress it in quantum Hall edge channels.

Findings

Weak-coupling materials with high electron velocity reduce intrinsic decoherence.

Extrinsic decoherence can be suppressed using specially designed sample geometries.

Proposes a realistic setup for testing decoherence control in experiments.

Abstract

Although interesting per se, decoherence and relaxation of single-electron excitations induced by strong effective screened Coulomb interactions in Quantum Hall edge channels are an important challenge for the applications of electron quantum optics in quantum information and quantum sensing. In this paper, we study intrinsic single-electron decoherence within an ideal single-electron channel with long-range effective Coulomb interactions to determine the influence of the material and sample properties. We find that weak-coupling materials characterized by a high velocity of hot-electron excitations may offer interesting perspectives for limiting intrinsic decoherence due to electron/electron interactions. We discuss quantitively how extrinsic decoherence due to the coupling with the channel's electromagnetic environment can be efficiently inhibited in specially designed samples at $\nu=2$ with one closed edge channel and we propose a realistic geometry for testing decoherence control in an Hong Ou Mandel experiment.