预报单光子源诱骗态量子密钥产生率及数值计算

Quantum Key Generation Rate of Decoy State Quantum Key Distribution with Heralded Single-photon Source

独立推导预报单光子源诱骗态量子密钥分发的密钥产生率计算公式,讨论密钥产生率和发送端探测效率的关系;进行弱相干光和预报单光子源诱骗态量子密钥分发的最优强度估计和密钥产生率数值计算.结果表明,预报单光子源诱骗态量子密钥分发的密钥产生率随着发送端探测效率的增加而增加,其安全通信距离与完美单光子源的通信距离一致;诱骗态量子密钥分发可提高安全通信距离和密钥产生率;预报单光子源由于减少了暗计数的影响,进一步提高了安全通信距离.

Quantum key generation rate of decoy state quantum key distribution （QKD） with a heralded single-photon source （HSPS） is deduced. Relationship between quantum key generation rate and detection efficiency of sender is discussed. Optimal intensities and key generation rate of decoy state QKD with a weak coherent pulse （WCP） and an HSPS are analyzed. It shows that key generation rate increases with increase of detection efficiency of sender and its security distance is the same as with a perfect single photon source. Decoy state QKD increases security distance and key rate of QKD. Due to less dark counts QKD with HSPS works longer distance than WCP.