A multiplexed light-matter interface for fibre-based quantum networks

TL;DR

This paper demonstrates a fibre-based quantum memory capable of storing and manipulating heralded single photons at telecom wavelengths, advancing scalable quantum networks with integrated, multimode light-matter interfaces.

Contribution

It introduces a fully integrated, telecom-wavelength quantum memory with high time-bandwidth product and multimode capacity using erbium-doped fibre and quantum photonics technologies.

Findings

Quantum storage of heralded single photons achieved at telecom wavelength.

Demonstration of frequency-multimode storage and spectral-temporal photon manipulation.

Potential for scalable quantum networks with improved light-matter interfaces.

Abstract

Processing and distributing quantum information using photons through fibre-optic or free-space links is essential for building future quantum networks. The scalability needed for such networks can be achieved by employing photonic quantum states that are multiplexed into time and/or frequency, and light-matter interfaces that are able to store and process such states with large time-bandwidth product and multimode capacities. Despite important progress in developing such devices, the demonstration of these capabilities using non-classical light remains challenging. Employing the atomic frequency comb quantum memory protocol in a cryogenically cooled erbium-doped optical fibre, we report the quantum storage of heralded single photons at a telecom-wavelength (1.53 {\mu}m) with a time-bandwidth product approaching 800. Furthermore we demonstrate frequency-multimode storage as well as memory-based spectral-temporal photon manipulation. Notably, our demonstrations rely on fully integrated quantum technologies operating at telecommunication wavelengths, i.e. a fibre-pigtailed nonlinear waveguide for the generation of heralded single photons, an erbium-doped fibre for photon storage and manipulation, and fibre interfaced superconducting nanowire devices for efficient single photon detection. With improved storage efficiency, our light-matter interface may become a useful tool in future quantum networks.