Experimental single qubit quantum secret sharing in a fiber network configuration

Area of Science:

• Quantum Information Science
• Quantum Communication Security
• Photonics

Background:

• Quantum secret sharing (QSS) is crucial for secure multiparty communication.
• Existing QSS schemes often face challenges with distance and environmental stability.
• Birefringence in optical fibers can degrade quantum signal integrity.

Purpose of the Study:

• To present a robust single-photon quantum secret sharing (QSS) scheme.
• To demonstrate a design for multi-party QSS over long-distance fiber networks.
• To achieve polarization-insensitive phase modulation for practical QSS.

Main Methods:

• Implementation of a phase-encoded single-photon QSS protocol.
• Utilizing a 50 km single-mode fiber network.
• Automatic compensation for birefringence within the QSS system.

Main Results:

• A robust QSS scheme demonstrated for three-party implementations, extendable to more parties.
• Automatic birefringence compensation achieved.
• High visibility (99.4%) maintained over three hours without system adjustments.
• Demonstration of polarization-insensitive phase modulators.

Conclusions:

• The proposed QSS scheme offers high stability and robustness for practical quantum communication.
• The system's ability to compensate for birefringence is a significant advancement.
• The successful implementation over 50 km fiber highlights its potential for secure, long-distance quantum networks.