Quantum information splitting of a two-qubit Bell state using a four-qubit entangled state**Supported by Fundamental Research Funds for the Central Universi-ties (ZYGX2011J064), National Nature Science Foundation of China (60903157, 61133016), and National High Technology Joint Re-search Program of China (863 Program, 2011AA010706)

Abstract

A scheme is proposed for quantum information splitting of a two-qubit Bell state by using a four-qubit entangled state as a quantum channel. In the scenario, it is supposed that there are three legitimate parties, say Alice, Bob and Charlie. Alice is the sender of quantum information. Bob and Charlie are two agents. Alice first performs GHZ state measurement and tells Bob and Charlie the measurement results via a classical channel. It is impossible for Bob to reconstruct the original state with local operations unless help is obtained from Charlie. If Charlie allows Bob to reconstruct the original state information, he needs to perform a single-qubit measurement and tell Bob the measurement result. Using the measurement results from Alice and Charlie, Bob can reconstruct the original state. We also consider the problem of security attacks. This protocol is considered to be secure.