On-Demand and Tunable Andreev-Conversion of Single-Electron Charge Pulses

TL;DR

This paper proposes a tunable method to convert single-electron pulses into holes using Andreev processes in superconductor-based quantum circuits, enabling coherent electron-hole superpositions for quantum applications.

Contribution

It introduces a novel on-demand, tunable mechanism for electron-to-hole conversion via Andreev processes, utilizing Floquet-Nambu formalism and interferometric control in quantum Hall systems.

Findings

Demonstrates dynamic charge pulse conversion with Floquet-Nambu scattering

Shows controllable electron-hole superposition generation via magnetic flux

Confirms feasibility with current experimental technology

Abstract

Electron quantum optics explores coherent single-electron charge pulse propagation in electronic nanoscale circuits akin to table-top photon setups. While past experiments focused on normal-state conductors, incorporating superconductors holds promise for exploiting the electron-hole degree of freedom in quantum sensing applications and quantum information processing. Here, we propose and analyze an on-demand and tunable mechanism for converting single-electron pulses into holes through Andreev processes on a superconductor. We develop a Floquet-Nambu scattering formalism to demonstrate the dynamic conversion of charge pulses and the controllable generation of coherent electron-hole superpositions through interferometric magnetic flux control based on the chiral edge states of a quantum Hall sample. Our discussion covers optimal conditions in realistic scenarios, affirming the feasibility of our proposal with current technology.