With the widespread application of quantum communication technology,there is an urgent need to enhance unconditionally secure key rates and capacity.Measurement-device-independent quantum key distribution(MDI-QKD),pro...With the widespread application of quantum communication technology,there is an urgent need to enhance unconditionally secure key rates and capacity.Measurement-device-independent quantum key distribution(MDI-QKD),proven to be immune to detection-side channel attacks,is a secure and reliable quantum communication scheme.The core of this scheme is Hong–Ou–Mandle(HOM)interference,a quantum optical phenomenon with no classical analog,where identical photons meeting on a symmetric beam splitter(BS)undergo interference and bunching.Any differences in the degrees of freedom(frequency,arrival time,spectrum,polarization,and the average number of photons per pulse)between the photons will deteriorate the interference visibility.Here,we demonstrate 16-channel weak coherent pulses(WCPs)of HOM interference with all channels’interference visibility over 46%based on two independent frequency-post-aligned soliton microcombs(SMCs).In our experiment,full locking and frequency alignment of the comb teeth between the two SMCs were achieved through pump frequency stabilization,SMC repetition rate locking,and fine tuning of the repetition rate.This demonstrates the feasibility of using independently generated SMCs as multi-wavelength sources for quantum communication.Meanwhile,SMC can achieve hundreds of frequency-stable comb teeth by locking only two parameters,which further reduces the complexity of frequency locking and the need for finding sufficient suitable frequency references compared to independent laser arrays.展开更多
逆向发动机常用于对飞行器进行减速或分离。为研究高空稀薄条件下逆向发动机喷流和自由来流的相互作用,构建了由两个逆向喷流和高超声速自由来流相互干扰形成的稀薄流场。通过直接模拟Monte Carlo(direct simulation Monte Carlo,DSMC)...逆向发动机常用于对飞行器进行减速或分离。为研究高空稀薄条件下逆向发动机喷流和自由来流的相互作用,构建了由两个逆向喷流和高超声速自由来流相互干扰形成的稀薄流场。通过直接模拟Monte Carlo(direct simulation Monte Carlo,DSMC)仿真发现在稀薄来流条件下会形成大面积相互干扰区,且该干扰区存在严重非定常流动现象。初步分析认为,该干扰区的范围和非定常演化过程与自由来流动能和逆向发动机喷流流量紧密相关。展开更多
基金Innovation Program for Quantum Science and Technology(2021ZD0300701,2021ZD0301500)CAS Project for Young Scientists in Basic Research(YSBR-069)+1 种基金National Natural Science Foundation of China(62075238,62205036)National Key Research and Development Program of China(2021YFB2800603)。
文摘With the widespread application of quantum communication technology,there is an urgent need to enhance unconditionally secure key rates and capacity.Measurement-device-independent quantum key distribution(MDI-QKD),proven to be immune to detection-side channel attacks,is a secure and reliable quantum communication scheme.The core of this scheme is Hong–Ou–Mandle(HOM)interference,a quantum optical phenomenon with no classical analog,where identical photons meeting on a symmetric beam splitter(BS)undergo interference and bunching.Any differences in the degrees of freedom(frequency,arrival time,spectrum,polarization,and the average number of photons per pulse)between the photons will deteriorate the interference visibility.Here,we demonstrate 16-channel weak coherent pulses(WCPs)of HOM interference with all channels’interference visibility over 46%based on two independent frequency-post-aligned soliton microcombs(SMCs).In our experiment,full locking and frequency alignment of the comb teeth between the two SMCs were achieved through pump frequency stabilization,SMC repetition rate locking,and fine tuning of the repetition rate.This demonstrates the feasibility of using independently generated SMCs as multi-wavelength sources for quantum communication.Meanwhile,SMC can achieve hundreds of frequency-stable comb teeth by locking only two parameters,which further reduces the complexity of frequency locking and the need for finding sufficient suitable frequency references compared to independent laser arrays.
文摘逆向发动机常用于对飞行器进行减速或分离。为研究高空稀薄条件下逆向发动机喷流和自由来流的相互作用,构建了由两个逆向喷流和高超声速自由来流相互干扰形成的稀薄流场。通过直接模拟Monte Carlo(direct simulation Monte Carlo,DSMC)仿真发现在稀薄来流条件下会形成大面积相互干扰区,且该干扰区存在严重非定常流动现象。初步分析认为,该干扰区的范围和非定常演化过程与自由来流动能和逆向发动机喷流流量紧密相关。
