In this study,we investigate the impact of substrates with distributed Bragg reflectors(DBRs)on the proximity effect during the fabrication of superconducting nanowire single-photon detectors(SNSPDs)using electron bea...In this study,we investigate the impact of substrates with distributed Bragg reflectors(DBRs)on the proximity effect during the fabrication of superconducting nanowire single-photon detectors(SNSPDs)using electron beam lithography.We compare the linewidth compression and line edge roughness of nanowires prepared on three different DBRs substrates.Additionally,we characterize the variations in switching current(I_(sw))and intrinsic detection efficiency(IDE)at a 2.2-K temperature.The results show that when the substrates are composed of low atomic number materials,such as Si and SiO2,the proximity effect is significantly mitigated.As a consequence,the lithography quality of nanowires is effectively improved,thus enhancing the IDE of SNSPDs.This study is expected to provide new insights into the fabrication of SNSPDs and lay the foundation for the preparation of high-performance and high-uniformity large-area devices.展开更多
Rapid detection and discrimination of single photons are pivotal in various applications,such as deep-space laser communication,high-rate quantum key distribution,and optical quantum computation.However,conventional s...Rapid detection and discrimination of single photons are pivotal in various applications,such as deep-space laser communication,high-rate quantum key distribution,and optical quantum computation.However,conventional single-photon detectors(SPDs),including semiconducting and recently developed superconducting detectors,have limited detection speed and photon number resolution(PNR),which pose significant challenges in practical applications.In this paper,we present an efficient,fast SPD with good PNR,which has 64 paralleled,sandwiched superconducting nanowires fabricated on a distributed Bragg reflector.The detector is operated in a compact Gifford–McMahon cryocooler that supports 64 electrical channels and has a minimum working temperature of 2.3 K.The combined detector system shows a functional nanowire yield of 61/64,a system detection efficiency of 90%at 1550 nm,and a maximum count rate of 5.2 GHz.Additionally,it has a maximum PNR of 61,corresponding to the operating nanowires.This SPD signifies a substantial improvement in quantum detector technology,with potential applications in deep-space laser communication,high-speed quantum communication,and fundamental quantum optics experiments.展开更多
基金Innovation Program for Quantum Science and Technology(No.2023ZD0300100)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)National Natural Science Foundation of China(U24A20320,and 12033007)for their financial support.
文摘In this study,we investigate the impact of substrates with distributed Bragg reflectors(DBRs)on the proximity effect during the fabrication of superconducting nanowire single-photon detectors(SNSPDs)using electron beam lithography.We compare the linewidth compression and line edge roughness of nanowires prepared on three different DBRs substrates.Additionally,we characterize the variations in switching current(I_(sw))and intrinsic detection efficiency(IDE)at a 2.2-K temperature.The results show that when the substrates are composed of low atomic number materials,such as Si and SiO2,the proximity effect is significantly mitigated.As a consequence,the lithography quality of nanowires is effectively improved,thus enhancing the IDE of SNSPDs.This study is expected to provide new insights into the fabrication of SNSPDs and lay the foundation for the preparation of high-performance and high-uniformity large-area devices.
基金Innovation Program for Quantum Science and Technology(2023ZD0300100)Shanghai Sailing Program(21YF1455500,21YF1455700,22YF1456500)+2 种基金Youth Innovation Promotion Association of the Chinese Academy of Sciences(2020241,2021230)Shanghai Municipal Science and Technology Major Project(2019SHZDZX01)National Natural Science Foundation of China(12033007,61827823,61971408).
文摘Rapid detection and discrimination of single photons are pivotal in various applications,such as deep-space laser communication,high-rate quantum key distribution,and optical quantum computation.However,conventional single-photon detectors(SPDs),including semiconducting and recently developed superconducting detectors,have limited detection speed and photon number resolution(PNR),which pose significant challenges in practical applications.In this paper,we present an efficient,fast SPD with good PNR,which has 64 paralleled,sandwiched superconducting nanowires fabricated on a distributed Bragg reflector.The detector is operated in a compact Gifford–McMahon cryocooler that supports 64 electrical channels and has a minimum working temperature of 2.3 K.The combined detector system shows a functional nanowire yield of 61/64,a system detection efficiency of 90%at 1550 nm,and a maximum count rate of 5.2 GHz.Additionally,it has a maximum PNR of 61,corresponding to the operating nanowires.This SPD signifies a substantial improvement in quantum detector technology,with potential applications in deep-space laser communication,high-speed quantum communication,and fundamental quantum optics experiments.
