Research On Quantum Communication Protocols Based On Cluster States

Quantum private communication is the technology that distributor uses the knowledge of quantum physics to encrypt information for transmitting and receiver obtains information by decrypting. Quantum cryptography has the advantage of provable for security and resistance for eavesdropping. Nowadays, as the rapidly development of communication technology, people have higher requirements for communication security, therefore lots of related issues are studied. For example, the design of new quantum communication protocols, security validation of quantum communication protocols and the improvement of quantum communication security. Cluster states is a new entangled state, it has strong character of entanglement and resist qubit loss, it can improve the security and efficiency of quantum cryptography communication. In order to study the application of cluster states in quantum cryptography communication, the main research fields and innovations of this paper are as follows.Based on cluster states, we propose a quantum secret sharing scheme. The sender encodes the classical secret on cluster states by Pauli operation and the receivers recover secret information by joint measurement. It inserts EPR pairs as decoy states into the sequences of state to prevent eavesdropping. It shows that this protocol is secure to resist attacks of intercept-measurement, intercept-resend and entanglement-measurement by security analysis. At the same time, one cluster state with four particles can share four bits of classical information, such that qubit efficiency approaches to100%.In addition, the paper also proposes a comparison scheme of quantum cryptography. The semi-honest third-party prepares a string of cluster states and splits them into two sequences sent to two receivers, the receivers encrypt their information that will be compared on cluster states, then they measure the particles and calculate the results. After that they sent the results to the semi-honest third-party, the semi-honest third-party calculates and publishes the results. By comparing the results, the receivers can know if their secret information is the same. The protocol is proved to be secure. It can resist well-known attacks including intercept-measurement, intercept-resend and entanglement-measurement and show that the program has a high efficiency through efficiency analysis.