Differential Quantum Key Distribution System Safety Analysis And Experimental Research

Quantum Key Distribution has attracted a lot of attention in recent yearsbecause of the promise it holds for faster and unconditionally secure futurecommunications between two legal paties. It is the most mature research fieldin the quantum information with great practical significance.Despite the significant progress in theory and experiments, eximiousachievements made in the performance of quantum cryptography system, thecommunication distance has been limited and communication bit rate remainslow, preventing the integration of QKD system into presenttelecommunication networks. Thus, current QKD system can not affordpractical application, especially commercial implement. Systems based onBB84 Protocol and some other similar protocols generate Key bits accordingto bases measurement results, which lead to low communication bitrate. Differential Phase Shift Quantum Key Distribution (DPS-QKD) presentedin 2002 has been a hot research field with its great advantages, such as higherprotocol effiency and communication bit rate.Differential Phase Shift Quantum Key Distribution and its security areresearched systematically in this paper. Improvement of DPS-QKD in systemstability ismade as well. Main contents are as follows:1. Security of DPS-QKD system is studied systematically in theory andexperiment ways. System performance under several typical attacks isdiscussed.2. A novel system setup based on DPS protocol is presented. Takingadvantage of Faraday Mirror, the setup can greatly improve system stabilityunder Gate Control Mode. The security and stability is generally discussed.3. Take a prospect into improvement methods and techniques for aDPS-QKD system.