Levitons in correlated nano-scale systems

TL;DR

This paper explores how Levitons, single-electron excitations generated by Lorentzian voltage drives, behave in strongly correlated nanoscale systems like fractional quantum Hall states and superconducting hybrids, revealing new interaction effects and potential quantum information applications.

Contribution

It provides a detailed analysis of Levitons in strongly correlated systems, extending their understanding beyond non-interacting cases and proposing new ways to generate entangled electron states.

Findings

Levitons interact with fractional anyons in quantum Hall systems.

Half-integer Levitons minimize noise in superconducting hybrid systems.

Energy-entangled electron states can be generated on-demand.

Abstract

in nanoscale systems in the presence of single-electron excitations generated by Lorentzian voltage drives, termed \textit{Levitons}. These excitations allow to realize the analog of quantum optics experiments using electrons instead of photons. Importantly, electrons in condensed matter systems are strongly affected by the presence of different types of non-trivial correlations, with no counterpart in the domain of photonic quantum optics. After providing a short introduction about Levitons in non-interacting systems, we focus on how they operate in the presence of two types of strong electronic correlations in nanoscale systems, such as those arising in the fractional quantum Hall effect or in superconducting systems. Specifically, we consider Levitons in a quantum Hall bar of the fractional quantum Hall effect, pinched by a quantum point contact, where anyons with fractional charge and statistics tunnel between opposite edges. In this case, a Leviton-Leviton interaction can be induced by the strongly correlated background. Concerning the effect of superconducting correlations on Levitons, we show that, in a normal metal system coupled to BCS superconductors, half integer Levitons minimize the excess noise in the Andreev regime. Interestingly, energy-entangled electron states can be realized on-demand in this type of hybrid setups by exploiting crossed Andreev reflection. The results exposed in this review have potential applications in the context of quantum information and computation with single-electron flying qubits.