The field · networking
Quantum networking
A quantum network moves entanglement, not bits — the resource behind quantum key distribution, distributed sensing, and eventually linking processors. The record below runs from a satellite to a live telecom network; the Bell tests these papers report are the same experiment the arcade's CHSH game lets you sample.
- Verified — published result
- Vendor-reported result
- Projection — roadmap target
- Opinion — named, dated
- Estimate — with caveats
- Contested — disputed in the record
- Preprint — not yet peer-reviewed
Milestones, by distance and by ingredient
Satellite entanglement over 1,203 km (Micius)
Verified — published resultYin et al. distributed entangled photon pairs from a satellite to two ground stations separated by 1,203 km — the distance record that established space links as a route around fiber loss.
Quantum memory nodes entangled over 35 km of Boston fiber
Verified — published resultKnaut et al. (Harvard/AWS) entangled silicon-vacancy centers in nanophotonic diamond cavities — nodes with electron and long-lived nuclear spin qubits — across a 35 km fiber loop deployed in the Boston urban environment, plus 40 km spools. Memory nodes, not just photons, are what a repeater network needs.
Entanglement on a live telecom network, alongside classical traffic
Verified — published resultSena et al. ran polarization-entangled photons through Deutsche Telekom's Berlin metropolitan fibers over selectable paths from 10 m to 60 km (extended to ~100 km), at 1324 nm coexisting with bidirectional C-band classical traffic on the same fibers. Bell-state fidelities of 85–99%, CHSH S between 2.36 and 2.74, and under 1.5% downtime across multi-day runs — the same Bell test the arcade lets you run.
8,235 stored modes of entanglement across Geneva
Preprint — not yet peer-reviewedRodriguez, Nicolas, Afzelius et al. distributed entanglement over 5.66 km of the Geneva metropolitan network while storing 8,235 temporal modes for 63 µs in a quantum memory (16,340 modes for 125 µs in the lab). Multimode memories are the throughput ingredient a quantum repeater requires. A preprint at the time of checking.
What is not yet built
No quantum-repeater network — entanglement distributed over long distance by chaining memory nodes, without trusted intermediate sites — has been deployed at scale as of the check date. The entries above are the components: space links, memory nodes, live-fiber coexistence, and multimode storage.