Quantum Private Query Using W State

Abstract

With the rapid development of computer-related technology, how to realize privacy query between both parties becomes very important. In this paper, we propose a quantum privacy query protocol based on W state, compared with the GHZ state, the W state is more robust and easier to prepare, the quantum circuit for preparing W state is also given. The protocol makes use of the correlation after entangled state measurement, and enables the querying party to obtain only one secret key information with the assistance of a third party, thus compared with existing schemes, this scheme eliminates the need for classic post-processing operations and can resist joint measurement attacks. In addition, the proposed protocol has two security checks, which can well resist ancilla particle attacks and entanglement measurement attacks by third parties and external intruders participating in the protocol. Therefore, the proposal of this protocol is very necessary.