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Updated: Dec 27, 2025
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
8.9K
Polarization design for ground-to-satellite quantum entanglement distribution
Optics Express
|March 3, 2020
Summary
This study demonstrates efficient ground-to-satellite quantum communication using a high-fidelity antenna design and polarization compensation. Entanglement distribution achieved a Bell inequality violation, proving the system
Area of Science:
- Quantum communication
- Quantum entanglement
- Satellite-based quantum networks
Background:
- Long-distance quantum communication relies on high-fidelity transmission of polarization-encoded qubits.
- Satellite channels enable quantum communication over thousands of kilometers.
Purpose of the Study:
- To develop an efficient uplink quantum communication system from ground to satellite.
- To achieve high-fidelity polarization transmission for quantum information.
Main Methods:
- Designed and tested a transmitting antenna with a high polarization extinction ratio (887:1).
- Implemented a polarization-compensation scheme to counteract satellite motion effects.
- Demonstrated entanglement distribution between ground and satellite.
Main Results:
- Achieved an average polarization extinction ratio of 887:1 in local tests.
- Polarization-compensation scheme demonstrated a fidelity exceeding 0.995 ± 0.001.
- Successfully distributed ground-to-satellite entanglement, violating Bell inequality by 2.312 ± 0.096.
Conclusions:
- The developed antenna and compensation scheme enable high-fidelity uplink quantum communication.
- Demonstrated the feasibility of satellite-based quantum communication with entanglement distribution.
- Results surpass classical limits, paving the way for secure long-distance quantum networks.
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