Random numbers are one of the key foundations of cryptography.This work implements a discrete quantum random number generator(QRNG)based on the tunneling effect of electrons in an avalanche photo diode.Without any pos...Random numbers are one of the key foundations of cryptography.This work implements a discrete quantum random number generator(QRNG)based on the tunneling effect of electrons in an avalanche photo diode.Without any post-processing and conditioning,this QRNG can output raw sequences at a rate of 100 Mbps.Remarkably,the statistical min-entropy of the 8,000,000 bits sequence reaches 0.9944 bits/bit,and the min-entropy validated by NIST SP 800-90B reaches 0.9872 bits/bit.This metric is currently the highest value we have investigated for QRNG raw sequences.Moreover,this QRNG can continuously and stably output raw sequences with high randomness over extended periods.The system produced a continuous output of 1,174 Gbits raw sequence for a duration of 11,744 s,with every 8 Mbits forming a unit to obtain a statistical min-entropy distribution with an average value of 0.9892 bits/bit.The statistical min-entropy of all data(1,174 Gbits)achieves the value of0.9951 bits/bit.This QRNG can produce high-quality raw sequences with good randomness and stability.It has the potential to meet the high demand in cryptography for random numbers with high quality.展开更多
Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections...Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections of the sender and analyze the possible attack strategies of Eve.Firstly,we present a quantized model for distinguishability of decoy states caused by intensity modulation.Besides,considering that Eve may control the preparation of states through hidden variables,we evaluate the security of preparation in practical quantum key distribution(QKD)scheme based on the weak-randomness model.Finally,we analyze the influence of the distinguishability of decoy state to secure key rate,for Eve may conduct the beam splitting attack and control the channel attenuation of different parts.Through the simulation,it can be seen that the secure key rate is sensitive to the distinguishability of decoy state and weak randomness,especially when Eve can control the channel attenuation.展开更多
目的探讨中心性肥胖与肝癌的关系。方法腰围、经BMI矫正的腰围、臀围、经BMI校正的臀围、腰臀比和经BMI校正的腰臀比相关的全基因组关联分析(genome wide association study,GWAS)数据来自欧洲一个包含224459个样本的大型数据库。内脏...目的探讨中心性肥胖与肝癌的关系。方法腰围、经BMI矫正的腰围、臀围、经BMI校正的臀围、腰臀比和经BMI校正的腰臀比相关的全基因组关联分析(genome wide association study,GWAS)数据来自欧洲一个包含224459个样本的大型数据库。内脏脂肪体积数据集来自欧洲数据库,包括32860名欧洲受试者的9275407个单核苷酸多态性(single nucleotide polymorphism,SNP)位点信息。肝癌的数据集来自英国生物银行数据库,包括372184名欧洲受试者的汇总数据。对获得的数据集进行两样本孟德尔随机化研究。结果逆方差加权法(IVW)分析结果显示,经BMI矫正的腰围会增加肝癌发生风险(OR=1.001,95%CI:1.000~1.001,P=0.024),且被加权中位数(WM)分析(OR=1.001,95%CI:1.000~1.002,P=0.020)证实,但在MR-Egger回归(OR=1.002,95%CI:0.999~1.004,P=0.135)中未被证实。其他中心性肥胖指标与肝癌无关。结论不同中心性肥胖指标与肝癌的相关性存在差异。经BMI矫正的腰围可能会导致肝癌发生,表明在相对较瘦的人群中,中心性肥胖与肝癌发生相关,且可能存在因果关系。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.51727805)。
文摘Random numbers are one of the key foundations of cryptography.This work implements a discrete quantum random number generator(QRNG)based on the tunneling effect of electrons in an avalanche photo diode.Without any post-processing and conditioning,this QRNG can output raw sequences at a rate of 100 Mbps.Remarkably,the statistical min-entropy of the 8,000,000 bits sequence reaches 0.9944 bits/bit,and the min-entropy validated by NIST SP 800-90B reaches 0.9872 bits/bit.This metric is currently the highest value we have investigated for QRNG raw sequences.Moreover,this QRNG can continuously and stably output raw sequences with high randomness over extended periods.The system produced a continuous output of 1,174 Gbits raw sequence for a duration of 11,744 s,with every 8 Mbits forming a unit to obtain a statistical min-entropy distribution with an average value of 0.9892 bits/bit.The statistical min-entropy of all data(1,174 Gbits)achieves the value of0.9951 bits/bit.This QRNG can produce high-quality raw sequences with good randomness and stability.It has the potential to meet the high demand in cryptography for random numbers with high quality.
基金the National Key Research and Development Program of China(Grant No.2020YFA0309702)NSAF(Grant No.U2130205)+3 种基金the National Natural Science Foundation of China(Grant Nos.62101597,61605248,and 61505261)the China Postdoctoral Science Foundation(Grant No.2021M691536)the Natural Science Foundation of Henan(Grant Nos.202300410534 and 202300410532)the Anhui Initiative in Quantum Information Technologies。
文摘Quantum key distribution provides an unconditional secure key sharing method in theory,but the imperfect factors of practical devices will bring security vulnerabilities.In this paper,we characterize the imperfections of the sender and analyze the possible attack strategies of Eve.Firstly,we present a quantized model for distinguishability of decoy states caused by intensity modulation.Besides,considering that Eve may control the preparation of states through hidden variables,we evaluate the security of preparation in practical quantum key distribution(QKD)scheme based on the weak-randomness model.Finally,we analyze the influence of the distinguishability of decoy state to secure key rate,for Eve may conduct the beam splitting attack and control the channel attenuation of different parts.Through the simulation,it can be seen that the secure key rate is sensitive to the distinguishability of decoy state and weak randomness,especially when Eve can control the channel attenuation.
