Quantum secret sharing (QSS) is one of the basic communication primitives in future quantum networks which addresses part of the basic cryptographic tasks of multiparty communication and computation. Nevertheless, it is a challenge to provide a practical QSS protocol with security against general attacks. A QSS protocol that balances security and practicality is still lacking. Here, we propose a QSS protocol with simple phase encoding of coherent states among three parties. Removing the requirement of impractical entangled resources and the need for phase randomization, our protocol can be implemented with accessible technology. We provide the finite-key analysis against coherent attacks and implement a proof-of-principle experiment to demonstrate our scheme's feasibility. Our scheme achieves a key rate of 85.3 bps under a 35 dB channel loss. Combined with security against general attacks and accessible technology, our protocol is a promising candidate for practical multiparty quantum communication networks.

翻译：量子秘密共享（QSS）是未来量子网络中基本的通信原语之一，它解决了多方通信与计算中的部分基础密码学任务。然而，提供一种可抵御一般攻击的实用化QSS协议仍是挑战，目前尚缺乏能够兼顾安全性与实用性的QSS协议。本文提出了一种三方间基于简单相干态相位编码的QSS协议。该协议无需使用不切实际的纠缠资源和相位随机化操作，可利用现有技术实现。我们给出了针对相干攻击的有限密钥分析，并通过原理验证实验证明了方案的可行性。在35 dB信道损耗下，该方案实现了85.3 bps的密钥率。结合对一般攻击的安全性与现有技术的易实现性，本文提出的协议有望成为实用化多方量子通信网络的候选方案。