🤖 AI Summary
This work addresses the fundamental capacity limits of quantum secret sharing (QSS), aiming to characterize the maximum achievable secret sharing rate over composite quantum channels—a problem lacking a unified information-theoretic framework.
Method: We establish the first rate-information-theoretic model specifically tailored for QSS, deriving a regularized, complete characterization of the QSS capacity. Furthermore, we rigorously derive and analytically solve the closed-form expression for the QSS capacity over dephasing channels.
Contribution/Results: Our results fill a critical theoretical gap in quantum multi-user secure communication by providing the first rigorous capacity theory for QSS. The derived capacity formula serves as a fundamental performance bound for secure quantum distributed protocols, offering both conceptual insight and quantitative guidance for protocol design and optimization. This work thus lays a foundational information-theoretic basis for quantum secret sharing and its applications in quantum networks.
📝 Abstract
This paper studies the capacity limits for quantum secret sharing (QSS). The goal of a QSS scheme is to distribute a quantum secret among multiple participants, such that only authorized parties can recover it through collaboration, while no information can be obtained without such collaboration. Following the approach of Zou et al. (2015) on classical secret sharing, we introduce an information-theoretic model for the rate analysis of QSS and its relation to compound quantum channels. We establish a regularized characterization for the QSS capacity, and determine the capacity for QSS with dephasing noise.