PHYSICS / QUANTUM COMMUNICATION

LR-LONGEST-DISTANCE-QUANTUM-KEY-DISTRIBUTIONOPEN LIMIT

Longest-distance quantum key distribution via satellite

Name: Longest-distance quantum key distribution via satellite
Creator: Limits Registry
Published: 2020-06-15T00:00:00.000Z
Keywords: PHYSICS / QUANTUM COMMUNICATION

China's Micius satellite, launched in 2016, distributed entangled photon pairs to ground stations in Delingha and Lijiang, Nanshan and Graz (Austria), enabling a 2020 demonstration of intercontinental quantum-key-distribution-secured communication across roughly 7,600 km between Beijing and Vienna — the longest-distance quantum key distribution link demonstrated to date, relying on trusted-node/satellite relay rather than a single unbroken entangled link.

— page viewsSpecification version 1Published 2020-06-151 evidence records

About this problem

The question, scope, and sources behind this Registry record.

Description

Formal question

The greatest ground-to-ground distance over which secure quantum key distribution has been demonstrated using a satellite as an entangled-photon relay.

Scope & constraints

Current published specification applies.

Primary sources

Nature — Entanglement-based secure quantum cryptography over 1,120 kilometres / Micius satellite intercontinental QKD — Longest-distance quantum key distribution via satellite University of Science and Technology of China, Hefei, China

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Scope matches the published specificationNo parameters changed

What we know

Current frontiers derived from accepted Claims.

Best demonstrated value7600

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Claims

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2026

CLM-LONGEST-DISTANCE-QUANTUM-KEY-DISTRIBUTION= 7600CONSTRUCTIONEntangled photon pairs generated and beamed from the Micius satellite to separated ground telescopes, with quantum key distribution protocols (BB84 or entanglement-based E91) implemented over the free-space optical links.Evidence quality: PAPER · Source: Nature — Entanglement-based secure quantum cryptography over 1,120 kilometres / Micius satellite intercontinental QKD — Longest-distance quantum key distribution via satellite ↗

SOURCE CONFIRMED

Timeline

The frontier as it changed over time.

How this frontier is derived

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Longest-distance quantum key distribution via satellite

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Longest-distance quantum key distribution via satellite

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