Long-Distance Measurement-Device-Independent Multiparty Quantum Communication

TL;DR

This paper proposes a practical scheme for distributing GHZ entanglement over 100 km, enhancing multiparty quantum communication by combining decoy-state and measurement-device-independent protocols.

Contribution

It introduces a feasible method for long-distance GHZ entanglement distribution, addressing current experimental limitations in multiparty quantum communication.

Findings

GHZ entanglement can be distributed over 100 km with current technology.

The scheme combines decoy-state and measurement-device-independent protocols.

This approach paves the way for practical multiparty quantum communication.

Abstract

The Greenberger-Horne-Zeilinger (GHZ) entanglement, originally introduced to uncover the extreme violation of local realism against quantum mechanics, is an important resource for multiparty quantum communication tasks. But the low intensity and fragility of the GHZ entanglement source in current conditions have made the practical applications of these multiparty tasks an experimental challenge. Here we propose a feasible scheme for practically distributing the post-selected GHZ entanglement over a distance of more than 100 km for experimentally accessible parameter regimes. Combining the decoy-state and measurement-device-independent protocols for quantum key distribution, we anticipate that our proposal suggests an important avenue for practical multiparty quantum communication.