Non-line-of-sight(NLOS)imaging has potential in autonomous driving,robotic vision,and medical imaging,but it is hindered by extensive scans.In this work,we provide a time-multiplexing NLOS imaging scheme that is desig...Non-line-of-sight(NLOS)imaging has potential in autonomous driving,robotic vision,and medical imaging,but it is hindered by extensive scans.In this work,we provide a time-multiplexing NLOS imaging scheme that is designed to reduce the number of scans on the relay surface.The approach introduces a time delay at the transmitting end,allowing two laser pulses with different delays to be sent per period and enabling simultaneous acquisition of data from multiple sampling points.Additionally,proof-of-concept experiments validate the feasibility of this approach,achieving reconstruction with half the scans.These results demonstrate a promising strategy for real-time NLOS imaging.展开更多
Integrated photonics provides a route to both miniaturization of quantum key distribution(QKD)devices and enhancing their performance.A key element for achieving discrete-variable QKD is a singlephoton detector.It is ...Integrated photonics provides a route to both miniaturization of quantum key distribution(QKD)devices and enhancing their performance.A key element for achieving discrete-variable QKD is a singlephoton detector.It is highly desirable to integrate detectors onto a photonic chip to enable the realization of practical and scalable quantum networks.We realize a heterogeneously integrated,superconducting silicon-photonic chip.Harnessing the unique high-speed feature of our optical waveguide-integrated superconducting detector,we perform the first optimal Bell-state measurement(BSM)of time-bin encoded qubits generated from two independent lasers.The optimal BSM enables an increased key rate of measurement-device-independent QKD(MDI-QKD),which is immune to all attacks against the detection system and hence provides the basis for a QKD network with untrusted relays.Together with the timemultiplexed technique,we have enhanced the sifted key rate by almost one order of magnitude.With a 125-MHz clock rate,we obtain a secure key rate of 6.166 kbps over 24.0 dB loss,which is comparable to the state-of-the-art MDI-QKD experimental results with a GHz clock rate.Combined with integrated QKD transmitters,a scalable,chip-based,and cost-effective QKD network should become realizable in the near future.展开更多
基金supported by the National Natural Science Foundation of China(No.62271468)。
文摘Non-line-of-sight(NLOS)imaging has potential in autonomous driving,robotic vision,and medical imaging,but it is hindered by extensive scans.In this work,we provide a time-multiplexing NLOS imaging scheme that is designed to reduce the number of scans on the relay surface.The approach introduces a time delay at the transmitting end,allowing two laser pulses with different delays to be sent per period and enabling simultaneous acquisition of data from multiple sampling points.Additionally,proof-of-concept experiments validate the feasibility of this approach,achieving reconstruction with half the scans.These results demonstrate a promising strategy for real-time NLOS imaging.
基金supported by the National Key Research and Development Program of China(Nos.2017YFA0303704,2019YFA0308700,and 2017YFA0304002)the National Natural Science Foundation of China(Nos.11690032,11321063,and 12033002)+2 种基金the NSFC-BRICS(No.61961146001)the Leading-Edge Technology Program of Jiangsu Natural Science Foundation(No.BK20192001)the Fundamental Research Funds for the Central Universities.
文摘Integrated photonics provides a route to both miniaturization of quantum key distribution(QKD)devices and enhancing their performance.A key element for achieving discrete-variable QKD is a singlephoton detector.It is highly desirable to integrate detectors onto a photonic chip to enable the realization of practical and scalable quantum networks.We realize a heterogeneously integrated,superconducting silicon-photonic chip.Harnessing the unique high-speed feature of our optical waveguide-integrated superconducting detector,we perform the first optimal Bell-state measurement(BSM)of time-bin encoded qubits generated from two independent lasers.The optimal BSM enables an increased key rate of measurement-device-independent QKD(MDI-QKD),which is immune to all attacks against the detection system and hence provides the basis for a QKD network with untrusted relays.Together with the timemultiplexed technique,we have enhanced the sifted key rate by almost one order of magnitude.With a 125-MHz clock rate,we obtain a secure key rate of 6.166 kbps over 24.0 dB loss,which is comparable to the state-of-the-art MDI-QKD experimental results with a GHz clock rate.Combined with integrated QKD transmitters,a scalable,chip-based,and cost-effective QKD network should become realizable in the near future.
