The development of quantum networks is paramount towards practical and secure communications.Quantum digital signatures(QDS)offer an information-theoretically secure solution for ensuring data integrity,authenticity,a...The development of quantum networks is paramount towards practical and secure communications.Quantum digital signatures(QDS)offer an information-theoretically secure solution for ensuring data integrity,authenticity,and nonrepudiation,rapidly growing from proof-of-concept to robust demonstrations.However,previous QDS systems relied on expensive and bulky optical equipment,limiting large-scale deployment and reconfigurable networking construction.Here,we introduce and verify a chip-based QDS network,placing the complicated and expensive measurement devices in the central relay while each user needs only a low-cost transmitter.We demonstrate the network with a three-node setup using an integrated encoder chip and decoder chip.By developing a 1-decoy-state one-time universal hashing-QDS protocol,we achieve a maximum signature rate of 0.0414 times per second for a 1 Mbit messages over fiber distances up to 200 km,surpassing all current state-of-the-art QDS experiments.This study validates the feasibility of chip-based QDS,paving the way for large-scale deployment and integration with existing fiber infrastructure.展开更多
Integrated photonics provides a promising platform for quantum key distribution(QKD)system in terms of miniaturization,robustness,and scalability.Tremendous QKD works based on integrated photonics have been reported.N...Integrated photonics provides a promising platform for quantum key distribution(QKD)system in terms of miniaturization,robustness,and scalability.Tremendous QKD works based on integrated photonics have been reported.Nonetheless,most current chip-based QKD implementations require additional off-chip hardware to demodulate quantum states or perform auxiliary tasks such as time synchronization and polarization basis tracking.Here,we report a demonstration of resource-efficient chip-based BB84 QKD with a silicon-based encoder and a decoder.In our scheme,the time synchronization and polarization compensation are implemented relying on the preparation and measurement of the quantum states generated by on-chip devices;thus,we need no additional hardware.The experimental tests show that our scheme is highly stable with a low intrinsic quantum bit error rate of 0.50%±0.02%in a 6 h continuous run.Furthermore,over a commercial fiber channel up to150 km,the system enables the realization of secure key distribution at a rate of 866 bit/s.Our demonstration paves the way for a low-cost,wafer-scale manufactured QKD system.展开更多
Silicon-based polarization-encoding quantum key distribution(QKD)has been extensively studied due to its advantageous characteris-tics of its low cost and robustness.However,given the difficulty of fabricating polariz...Silicon-based polarization-encoding quantum key distribution(QKD)has been extensively studied due to its advantageous characteris-tics of its low cost and robustness.However,given the difficulty of fabricating polarized independent components on the chip,previ-ous studies have only adopted off-chip devices to demodulate the quantum states or perform polarization compensation.In the cur-rent work,a fully chip-based decoder for polarization-encoding QKD was proposed.The chip realized a polarization state analyzer and compensated for the BB84 protocol without the requirement of additional hardware,which was based on a polarization-to-path conversion method utilizing a polarization splitter-rotator.The chip was fabricated adopting a standard silicon photonics foundry,which was of a compact design and suitable for mass production.In the experimental stability test,an average quantum bit error rate of 0.59%was achieved through continuous operation for 10 h with-out any polarization feedback.Furthermore,the chip enabled the automatic compensation of the fiber polarization drift when utiliz-ing the developed feedback algorithm,which was emulated by a ran-dom fiber polarization scrambler.Moreover,a finite-key secret rate of 240 bps over a fiber spool of 100 km was achieved in the case of the QKD demonstration.This study marks an important step to-ward the integrated,practical,and large-scale deployment of QKD systems.展开更多
基金supported by the National Natural Science Foundation of China(Nos.12274223,62171144,62031024,and 62171485)the Guangxi Science Foundation(No.2021GXNSFAA220011)+1 种基金the Open Fund of IPOC(BUPT)(No.IPOC2021A02)the Innovation Project of Guangxi Graduate Education(No.YCBZ2024002).
文摘The development of quantum networks is paramount towards practical and secure communications.Quantum digital signatures(QDS)offer an information-theoretically secure solution for ensuring data integrity,authenticity,and nonrepudiation,rapidly growing from proof-of-concept to robust demonstrations.However,previous QDS systems relied on expensive and bulky optical equipment,limiting large-scale deployment and reconfigurable networking construction.Here,we introduce and verify a chip-based QDS network,placing the complicated and expensive measurement devices in the central relay while each user needs only a low-cost transmitter.We demonstrate the network with a three-node setup using an integrated encoder chip and decoder chip.By developing a 1-decoy-state one-time universal hashing-QDS protocol,we achieve a maximum signature rate of 0.0414 times per second for a 1 Mbit messages over fiber distances up to 200 km,surpassing all current state-of-the-art QDS experiments.This study validates the feasibility of chip-based QDS,paving the way for large-scale deployment and integration with existing fiber infrastructure.
基金National Natural Science Foundation of China(62171144,62031024)Guangxi Science Foundation(2021GXNSFAA220011)Open Fund of IPOC(BUPT)(IPOC2021A02)。
文摘Integrated photonics provides a promising platform for quantum key distribution(QKD)system in terms of miniaturization,robustness,and scalability.Tremendous QKD works based on integrated photonics have been reported.Nonetheless,most current chip-based QKD implementations require additional off-chip hardware to demodulate quantum states or perform auxiliary tasks such as time synchronization and polarization basis tracking.Here,we report a demonstration of resource-efficient chip-based BB84 QKD with a silicon-based encoder and a decoder.In our scheme,the time synchronization and polarization compensation are implemented relying on the preparation and measurement of the quantum states generated by on-chip devices;thus,we need no additional hardware.The experimental tests show that our scheme is highly stable with a low intrinsic quantum bit error rate of 0.50%±0.02%in a 6 h continuous run.Furthermore,over a commercial fiber channel up to150 km,the system enables the realization of secure key distribution at a rate of 866 bit/s.Our demonstration paves the way for a low-cost,wafer-scale manufactured QKD system.
基金This study was supported by the National Natural Science Founda-tion of China(Nos.62171144,62031024,and 62171485)the Guangxi Sci-ence Foundation(No.2021GXNSFAA220011)the Open Fund of IPOC(BUPT)(No.IPOC2021A02).
文摘Silicon-based polarization-encoding quantum key distribution(QKD)has been extensively studied due to its advantageous characteris-tics of its low cost and robustness.However,given the difficulty of fabricating polarized independent components on the chip,previ-ous studies have only adopted off-chip devices to demodulate the quantum states or perform polarization compensation.In the cur-rent work,a fully chip-based decoder for polarization-encoding QKD was proposed.The chip realized a polarization state analyzer and compensated for the BB84 protocol without the requirement of additional hardware,which was based on a polarization-to-path conversion method utilizing a polarization splitter-rotator.The chip was fabricated adopting a standard silicon photonics foundry,which was of a compact design and suitable for mass production.In the experimental stability test,an average quantum bit error rate of 0.59%was achieved through continuous operation for 10 h with-out any polarization feedback.Furthermore,the chip enabled the automatic compensation of the fiber polarization drift when utiliz-ing the developed feedback algorithm,which was emulated by a ran-dom fiber polarization scrambler.Moreover,a finite-key secret rate of 240 bps over a fiber spool of 100 km was achieved in the case of the QKD demonstration.This study marks an important step to-ward the integrated,practical,and large-scale deployment of QKD systems.
