Sharing a quantum secret without a trusted party

TL;DR

This paper introduces a quantum (k,n) threshold scheme that eliminates the need for a trusted party by allowing participants to independently contribute their private states to reconstruct the secret.

Contribution

It presents a novel quantum threshold scheme where participants generate and share the secret without relying on a trusted third party.

Findings

Secure quantum secret sharing without a trusted authority

Participants independently contribute to secret reconstruction

Scheme maintains security with fewer assumptions

Abstract

In a conventional quantum (k,n) threshold scheme, a trusted party shares a secret quantum state with n participants such that any k of those participants can cooperate to recover the original secret, while fewer than k participants obtain no information about the secret. In this paper we show how to construct a quantum (k,n) threshold scheme without the assistance of a trusted party, who generates and distributes shares among the participants. Instead, each participant chooses his private state and contributes the same to the determination of the final secret quantum state.