Quantum Information Splitting of An Arbitrary k-qubit Information Among n-agents Using Greenberger-Horne-Zeilinger States

Abstract

Quantum Information Splitting (QIS) is the quantum cryptographic primitive using which the owner of a quantum information (or quantum state), known as the dealer, creates n-shares of the information and distributes them among n-participants, known as agents. Moreover, the QIS protocols ensure that the original information can be regenerated only when the dealer and all of the agents cooperate. To the best of our knowledge, no generalized QIS protocol exists that splits an arbitrary k-qubit information among arbitrary n-agents using Greenberger-Horne-Zeilinger (GHZ) state as the quantum channel where each agent is equally capable of regenerating the original information. In this paper, we propose a protocol for QIS of an arbitrary k-qubit information among n-agents using a quantum channel composed of k copies of \((n+1)\)-qubit GHZ state. The proposed protocol is symmetric in the sense that each agent is equally capable of regenerating the information. However, owing to the no-cloning theorem, the dealer and agents unanimously select exactly one agent to regenerate the original information. The proposed protocol describes the strategy used by the dealer for share generation and the strategy used by the selected agent to regenerate the information with the cooperation of the dealer and remaining agents.