Cavity-mediated electron-photon pairs

TL;DR

This paper demonstrates the generation of electron-photon pairs via phase-matched interactions with a microresonator, enabling quantum correlations useful for imaging and quantum information applications.

Contribution

It introduces a novel method for creating electron-photon pairs using free electrons and a photonic microresonator, advancing free-electron quantum optics.

Findings

Achieved two-orders of magnitude contrast improvement in cavity-mode mapping.

Demonstrated correlation-enhanced imaging using electron-photon pairs.

Established a pathway for quantum-enhanced imaging and entanglement with free electrons.

Abstract

Advancing quantum information, communication and sensing relies on the generation and control of quantum correlations in complementary degrees of freedom. Here, we demonstrate the preparation of electron-photon pair states using the phase-matched interaction of free electrons with the evanescent vacuum field of a photonic-chip-based optical microresonator. Spontaneous inelastic scattering produces intracavity photons coincident with energy-shifted electrons. Harnessing these pairs for correlation-enhanced imaging, we achieve a two-orders of magnitude contrast improvement in cavity-mode mapping by coincidence-gated electron spectroscopy. This parametric pair-state preparation will underpin the future development of free-electron quantum optics, providing a pathway to quantum-enhanced imaging, electron-photon entanglement, and heralded single-electron and Fock-state photon sources.