New Quantum Private Comparison Protocol Using χ-Type State

Abstract

We present a new quantum private comparison protocol based on the four-particle χ-type states. Different from previous protocols using the four-particle χ-type states, our protocol have some advantages. Without using the entangled character, we only need to prepare one type of χ-type state and Nχ-type states. And we use the Pauli local unitary operation on particles to encode the information and to extract information by measurement. We also discuss that our protocol can withstand all various kinds of outside attacks and participant attacks.