Transmission of light-matter entanglement over a metropolitan network

Abstract

We report on the transmission of telecom photons entangled with a multimode solid-state quantum memory over a deployed optical fiber in a metropolitan area. Photon pairs were generated through spontaneous parametric down-conversion, with one photon stored in a rare earth-based quantum memory, and the other, at telecommunication wavelengths, traveling through increasing distances of optical fibre, first in the laboratory and then outside in a deployed fibre loop. We measured highly-non-classical correlations between the stored and the telecom photons for storage times up to 25 $\mu$s and for a fibre separation up to 50 km. We also report light-matter entanglement with a two-qubit fidelity up to 88$\%$, which remains constant within error bars for all fibre lengths, showing that the telecom qubit does not suffer decoherence during the transmission. Finally, we moved the detection stage of the telecom photons to a different location placed 17 km away, and confirmed the non-classical correlations between the two photons. Our system was adapted to provide the transmission of precise detection times and synchronization signals over long quantum communication channels, providing the first steps for a future quantum network involving quantum memories and non-classical states.

References in corpus (19)

• The Quantum Internet
• An Elementary Quantum Network of Single Atoms in Optical Cavities
• Single-Photon Switching and Entanglement of Solid-State Qubits in an Integrated Nanophotonic System
• Realization of a multi-node quantum network of remote solid-state qubits
• Quantum Repeaters with Photon Pair Sources and Multi-Mode Memories
• Quantum Storage of Photonic Entanglement in a Crystal
• Quantum storage of entangled telecom-wavelength photons in an erbium-doped optical fibre
• A Quantum-Logic Gate between Distant Quantum-Network Modules
• Experimental realization of a multiplexed quantum memory with 225 individually accessible memory cells
• Cavity-enhanced storage in an optical spin-wave memory
• Quantum storage of polarization qubits in birefringent and anisotropically absorbing materials
• Wavevector multiplexed quantum memory via spatially-resolved single-photon detection
• Long-distance multiplexed quantum teleportation from a telecom photon to a solid-state qubit
• Approaches for a quantum memory at telecommunication wavelengths
• Elimination of Noise in Optically Rephased Photon Echoes
• Reliable coherent optical memory based on a laser-written waveguide
• Atomic frequency comb memory with spin wave storage in 153Eu3+:Y2SiO5
• Multicell Atomic Quantum Memory as a Hardware-Efficient Quantum Repeater Node
• On-demand multimode optical storage in a laser-written on-chip waveguide

Cited by in corpus (11)

• Distributed Quantum Computing: a Survey
• Metropolitan-scale heralded entanglement of solid-state qubits
• Fast delivery of heralded atom-photon quantum correlation over 12km fiber through multiplexing enhancement
• Quantum networks using rare-earth ions
• Standalone mobile quantum memory system
• Remote Quantum Networks based on Quantum Memories
• A Design Framework for the Simulation of Distributed Quantum Computing
• Multiplexed quantum repeaters based on single-photon interference with mild stabilization
• Space-division multiplexed phase compensation for quantum communication: concept and field demonstration
• Hybrid classical-quantum communication networks
• Quality assessment of quantum teleportation through the distribution of fidelity