Decoy-State Quantum Key Distribution over a Long-Distance High-Loss Underwater Free-Space Channel
arXiv:2004.06708 · doi:10.1103/PhysRevApplied.15.024060
Abstract
Atmospheric free space and fiber have been widely exploited as the channels for quantum communication, and have enabled inter-continent and inter-city applications. Air-sea free-space channel, being capable of linking the satellite-based quantum resource and underwater vehicle, has now become the last piece of the puzzle in building global quantum communication network. However, long-distance quantum communication penetrating water up to tens to hundreds of meters is extremely challenging due to the inevitable high loss. Here, we present an experimental demonstration of underwater decoy-state quantum key distribution against high loss, meanwhile keep a low quantum bit error rate less than 2.5% for different distances. By directly modulating blue-green lasers at a high speed of 50MHz and decoy-state protocol, we are able to for the first time reach a long-distance quantum key distribution that is unconditionally secure and can enable real-life air-sea quantum communication tasks. The demonstrated distance, even in coastal water of Jerlov types 2C, is up to 30 meters, about one-order improvement over the proof-in-principle demonstrations in previous experiments, and the channel loss is equivalent to 345-meter-long clean seawater of Jerlov type I, representing a key step forward to practical air-sea quantum communication.
arXiv comment9 pages, 8 figures, 3 tables
References in corpus (22)
- The Quantum Internet
- Simple Proof of Security of the BB84 Quantum Key Distribution Protocol
- Unconditional Security Of Quantum Key Distribution Over Arbitrarily Long Distances
- Satellite-to-ground quantum key distribution
- Quantum Key Distribution with High Loss: Toward Global Secure Communication
- Beating the PNS attack in practical quantum cryptography
- Overcoming the rate-distance barrier of quantum key distribution without using quantum repeaters
- Field test of quantum key distribution in the Tokyo QKD Network
- Practical Decoy State for Quantum Key Distribution
- Ground-to-satellite quantum teleportation
- Direct and full-scale experimental verifications towards ground-satellite quantum key distribution
- Satellite-to-ground quantum communication using a 50-kg-class micro-satellite
- Experimental quantum key distribution beyond the repeaterless secret key capacity
- Measurement-device-independent quantum key distribution over untrustful metropolitan network
- High-fidelity transmission of entanglement over a high-loss freespace channel
- Towards Quantum Communication in Free-Space Seawater
- All-fiber self-compensating polarization encoder for Quantum Key Distribution
- Towards satellite-based quantum-secure time transfer
- Characterization of an underwater channel for quantum communications in the Ottawa River
- Experimental investigation of quantum key distribution over water channel
- Low loss QKD optical scheme for fast polarization encoding
- Performance of Underwater Quantum Key Distribution with Polarization Encoding
Cited by in corpus (5)
- Breaking the Rate-Loss Bound of Quantum Key Distribution with Asynchronous Two-Photon Interference
- Experimental Demonstration of Underwater Decoy-state Quantum Key Distribution with All-optical Transmission
- On the Optimization of Underwater Quantum Key Distribution Systems with Time-Gated SPADs
- Quantum Key Distribution with Imperfections: Recent Advances in Security Proofs
- Practical underwater quantum key distribution based on decoy-state BB84 protocol