Decentralized continuous-variable quantum secret sharing

Quantum secret sharing (QSS) is a method that allows multiple users to obtain pieces of a secret key from a dealer, but the complete key can only be recovered if all users collaborate. However, the status of the dealer in the system brings potential security risks to the communication network. To solve this problem, we propose a decentralized quantum secret sharing (DQSS) scheme that allows any honest user in the system to become a dealer and send a partial key to other users through an insecure quantum channel. The position of the dealer in the user chain in this scheme is no longer limited to the end of the chain, but can be located at any position. This scheme can be realized with local local oscillator (LLO) using discretely modulated coherent states (DMCSs). With this approach, the multi-user quantum secret sharing scheme can be implemented with any honest user acting as a dealer in a quantum communication network.

Automated summary

Quantum secret sharing is a method that allows multiple users to share a secret key, but the dealer's position poses potential security risks. To address this issue, we propose a decentralized quantum secret sharing scheme where any honest user can act as the dealer in a quantum communication network.