The Performance Of Measurement Device Independent Quantum Key Distribution

The security of traditional cryptography is based on computational complexity.With the improvement of computer performance,the security of traditional cryptography is facing a huge challenge.Quantum communication is a combination of quantum theory and information theory and is absolutely safe in theory.Quantum key distribution,which is expected to realize true communication security,is the most mature and practical technology in quantum communication.However,due to practical factors such as imperfect experimental devices,there are some security vulnerabilities in the actual application of quantum key distribution.Although the actual light source has the problem of multiphoton and the actual detector also has the problem of detection,they are all solved well by the decoy state method and the measurement device independent quantum key distribution.The combination of the measurement device independent quantum key distribution and the decoy state method can realize secure communication under the realistic standard devices,so it has quickly become a hot spot at home and abroad.Based on the decoy state measurement device independent quantum key distribution,we further study the performance of three intensity decoy state measurement device independent quantum key distribution and satellite-based measurement device independent quantum key distribution through numerical simulation in this thesis.We first introduce the research background,research significance and research progress of quantum key distribution as well as the latest development of the measurement device independent quantum key distribution.Then we introduce the relevant theoretical knowledge of quantum key distribution.Based on this theoretical knowledge,the measurement device independent quantum key distribution is investigated in detail and relevant conclusions are obtained.The performance of the symmetrical channel of three-intensity decoy-state measurement device independent quantum key distribution using the central limit theorem statistical fluctuation analysis method is better than that of the asymmetrical channel.The intensity of decoy state has a more significant impact on performance than that of signal state.The optimal intensity value of the asymmetric channel satisfies a specific mathematical relationship.In addition,we combine measurement device independent quantum key distribution with satellite-to-ground communication.It is found that there is a certain probability distribution for the key rate of satellite-based measurement device independent quantum key distribution.In general,the higher the key rate,the lower the probability.Satellite-based measurement device independent quantum key distribution has a higher tolerance for misalignment error than dark count.These results may provide theoretical references for experiments and practical applications and then accelerate the practical process of quantum key distribution.