Differential Phase Shift Quantum Secret Sharing Using a Twin Field with Asymmetric Source Intensities

Area of Science:

• Quantum Information Science
• Quantum Cryptography
• Quantum Internet

Background:

• Quantum secret sharing is crucial for quantum internet security.
• Existing differential phase shift protocols struggle with asymmetric channel transmittances.
• A need exists for practical quantum secret sharing solutions resilient to channel imperfections.

Purpose of the Study:

• To develop a practical differential phase shift quantum secret sharing protocol.
• To address performance limitations of previous protocols in asymmetric channels.
• To enhance security and key rates in quantum secret sharing applications.

Main Methods:

• Proposed a differential phase shift quantum secret sharing protocol utilizing asymmetric source intensities.
• Conducted a security proof against individual attacks.
• Analyzed finite-key effects on protocol performance.

Main Results:

• The asymmetric protocol achieves key rates two orders of magnitude higher than the original protocol under specific conditions (14 km channel length difference).
• Demonstrated high key rates even with large channel length differences.
• Showcased significant robustness against finite-key effects.

Conclusions:

• The developed asymmetric quantum secret sharing protocol offers a practical and efficient solution for quantum internet applications.
• The protocol overcomes limitations of previous methods, providing enhanced performance and security.
• This work contributes to the real-world implementation of secure quantum communication.