The Characteristic Study Of Single Photon Source In Quantum Communication

Quantum Key Distribution(QKD)combined with the classic"one-time-one-density" encryption algorithm can deliver unconditional and secure information and thus has broad application prospects in the areas of national defense and commercial areas.Practical quantum key distribution system is one of the hot topics in the field of quantum information.After nearly 40 years of development,QKD has become more and more perfect in both theory and experiment.However,due to the limitation of current experimental conditions,the single-photon source in practical experiments cannot reach the ideal state,which leads to the fact that there may exist some security holes in the practical QKD system,which can be exploited by eavesdroppers so that the unconditional security of information cannot be achieved.The Measurement Device Independent Quantum Key Distribution(MDI-QKD)removes all side-channel attacks to ensure light source security and is considered to be the closest practical experimental solution.The full text is divided into six chapters.The research background and the latest development of quantum communication are introduced in the first chapter.The characteristics of quantum key distribution protocol are analyzed in the second chapter in detail,and the several current quantum key distribution protocols are introduced after.The optical fiber-based quantum key distribution system model is introduced in the third chapter,and then the performance of the finite light source system model and the untrusted light source system is analyzed and discussed;The impact of statistical fluctuations on the system performance in practical systems is analyzed in the chapter 4,as well as the statistics of the internal transmission rate fluctuation based on the optimization of the finite key.By considering the fluctuation statistics of parameter estimation,we analyzed the practicality of MDI-QKD.The system simulation analyzed in the chapter 5.Finally,the work summarization of this dissertation is introduced in the chapter 6 as well as looking forward to the future of quantum communication and possible problems.