Nano-optomechanical systems,capable of supporting enhanced light-matter interactions,have wide applications in studying quantum entanglement and quantum information processors.Yet,preparing optical telecomband entangl...Nano-optomechanical systems,capable of supporting enhanced light-matter interactions,have wide applications in studying quantum entanglement and quantum information processors.Yet,preparing optical telecomband entanglement within a single optomechanical nanobeam remains blank.We propose and design a triply resonant optomechanical nanobeam to generate steady-state entangled propagating optical modes and present its quantum-enhanced performance for teleportation-based quantum state transfer under realistic conditions.Remarkably,the entanglement quantified by logarithmic negativity can obtain E_(N)=1.Furthermore,with structural imperfections induced by realistic fabrication processes considered,the device still shows great robustness.Together with quantum interfaces between mechanical motion and solid-state qubit processors,the proposed device potentially paves the way for versatile nodes in long-distance quantum networks.展开更多
A fully connected quantum network with a wavelength division multiplexing architecture plays an increasingly pivotal role in quantum information technology.With such architecture,an entanglement-based network has been...A fully connected quantum network with a wavelength division multiplexing architecture plays an increasingly pivotal role in quantum information technology.With such architecture,an entanglement-based network has been demonstrated in which an entangled photon-pair source distributes quantum entanglement resources to many users.Despite these remarkable advances,the scalability of the architecture could be constrained by the finite spectrum resource,where&(N2)wavelength channels are needed to connect N users,thus impeding further progress in real-world scenarios.Here,we propose a scheme for the wavelength division multiplexing entanglement-based network using a state-multiplexing quantum light source.With a dual-pump configuration,the feasibility of our approach is demonstrated by generating state-multiplexing photon pairs at multiple wavelength channels with a silicon nitride microring resonator chip.In our demonstration,we establish a fully connected graph between four users with six wavelength channels—saving half of which without sacrificing functionality and performance of the secure communication.A total asymptotic secure key rate of 1946.9 bps is obtained by performing the BBM92 protocol with the distributed state.The network topology of our method has great potential for developing a scalable quantum network with significantly minimized infrastructure requirements.展开更多
Quantum entanglement networks have garnered significant attention due to the inherent security provided by quantum physics.The networks aim to connect a multitude of users with a high secure key rate(SKR).Fully connec...Quantum entanglement networks have garnered significant attention due to the inherent security provided by quantum physics.The networks aim to connect a multitude of users with a high secure key rate(SKR).Fully connected networks have been demonstrated using wavelength-division multiplexing architectures.However,the SKR of such networks remains challenging due to the limited brightness of quantum photon-pair sources and the loss introduced by cascaded filtering components.We present high-rate quantum entanglement networks that leverage a broadband quantum light source with high brightness and an industrygrade flexible wavelength-selective switching technique with uniform loss.By implementing the BBM92 protocol,we achieve an SKR of 28.19 kbps in a four-user network,representing a two-order-of-magnitude improvement over previous implementations.After transmission through a 40-km fiber spool,the SKR remains as high as 3.58 kbps and stays positive over distances up to 250 km.Furthermore,the flexibility of our scheme is illustrated by constructing a six-user network,achieving SKRs of 4.21 kbps and 0.45 kbps without and with a 40-km fiber spool,respectively.These results demonstrate a practical approach to enhancing the SKR and scalability in entanglement-based quantum networks,offering a feasible solution for deploying metropolitan and backbone quantum communication systems.展开更多
The reflection matrix optical coherence tomography(RM-OCT)method has made significant progress in extending imaging depth within scattering media.However,the current method of measuring the reflection matrix(RM)throug...The reflection matrix optical coherence tomography(RM-OCT)method has made significant progress in extending imaging depth within scattering media.However,the current method of measuring the reflection matrix(RM)through uniform sampling results in relatively long data collection time.This study demonstrates that the RM in scattering media exhibits sparsity.Consequently,a compressed sensing(CS)-based technique for measuring the RM is proposed and applied to RM-OCT images.Experimental results show that this method requires less than 50%of the traditional sampling data to recover target information within scattering media,thereby significantly reducing data acquisition time.These findings not only expand the theory of the RM but also provide a more efficient measurement approach.This advancement opens up broader applications for CS techniques in RM-OCT and holds great potential for improving imaging efficiency in scattering media.展开更多
We report a broadband energy-time entangled photon-pair source based on a fiber-pigtailed periodically poled lithium niobate[PPLN]waveguide,designed for applications in the quantum secure network.Utilizing the spontan...We report a broadband energy-time entangled photon-pair source based on a fiber-pigtailed periodically poled lithium niobate[PPLN]waveguide,designed for applications in the quantum secure network.Utilizing the spontaneous parametric down-conversion nonlinear optical process,the source generates entangled photon pairs within a wavelength range of64 nm in the telecom band at a pump wavelength of 770.3 nm.Photon pairs from eight paired International Telecommunication Union[ITU]channels are selected,and their correlation and entanglement properties are characterized.The measured coincidence counts of photon pairs from eight paired ITU channels are larger than 152.9 kHz when the coincidence-to-accidental ratios are greater than 260.Entanglement properties are measured through two-photon interference in the Franson interferometer,with all visibilities of interference curves exceeding 98.13%.Our demonstration provides a broadband energy-time entangled photon-pair source,contributing to the development of a large-scale quantum secure network.展开更多
The light–matter interface is an important building block for long-distance quantum networks.Towards a scalable quantum network with high-rate quantum information processing,it requires to develop integrated light–m...The light–matter interface is an important building block for long-distance quantum networks.Towards a scalable quantum network with high-rate quantum information processing,it requires to develop integrated light–matter interfaces with broadband and multiplexing capacities.Here we demonstrate a light–matter interface at the telecom band in an integrated system.A five-spectral-channel atomic-frequency-comb photonic memory is prepared on a laser-written Er^(3+):LiNbO_(3)chip.The bandwidth of each channel is 4 GHz with a channel spacing of 15 GHz.The signal photons from time-bin entangled photon pairs at the telecom band are sent into the on-chip memory and recalled after a storage time of 152 ns.The entanglement-preserving nature of our integrated quantum interface is assessed by an input/output fidelity of>92%for all five spectral channels.Our light–matter interfaces constitute a notable step forward toward a high-rate quantum network involving integrated devices.展开更多
基金supported by the Sichuan Science and Technology Program(Grant Nos.2022YFSY0061,2022YFSY0062,2022YFSY0063,2023YFSY0060,2023YFSY0058,and 2023YFSY0059)the National Key Research and Development Program of China(Grant No.2022YFA1405900)+1 种基金the National Natural Science Foundation of China(Grant Nos.92365106,62005039,91836102,U19A2076,12074058,and 62174010)the Innovation Program for Quantum Science and Technology(Grant Nos.2021ZD0300701 and 2021ZD0301702)。
文摘Nano-optomechanical systems,capable of supporting enhanced light-matter interactions,have wide applications in studying quantum entanglement and quantum information processors.Yet,preparing optical telecomband entanglement within a single optomechanical nanobeam remains blank.We propose and design a triply resonant optomechanical nanobeam to generate steady-state entangled propagating optical modes and present its quantum-enhanced performance for teleportation-based quantum state transfer under realistic conditions.Remarkably,the entanglement quantified by logarithmic negativity can obtain E_(N)=1.Furthermore,with structural imperfections induced by realistic fabrication processes considered,the device still shows great robustness.Together with quantum interfaces between mechanical motion and solid-state qubit processors,the proposed device potentially paves the way for versatile nodes in long-distance quantum networks.
基金supported by Sichuan Science and Technology Program(Nos.2022YFSY0061,2022YFSY0062,2022YFSY0063,2023YFSY0062,2023YFSY0058,2023NSFSC0048)the National Natural Science Foundation of China(Nos.62475039,62405046,92365106,62105371)Innovation Program for Quantum Science and Technology(No.2021ZD0300701).
文摘A fully connected quantum network with a wavelength division multiplexing architecture plays an increasingly pivotal role in quantum information technology.With such architecture,an entanglement-based network has been demonstrated in which an entangled photon-pair source distributes quantum entanglement resources to many users.Despite these remarkable advances,the scalability of the architecture could be constrained by the finite spectrum resource,where&(N2)wavelength channels are needed to connect N users,thus impeding further progress in real-world scenarios.Here,we propose a scheme for the wavelength division multiplexing entanglement-based network using a state-multiplexing quantum light source.With a dual-pump configuration,the feasibility of our approach is demonstrated by generating state-multiplexing photon pairs at multiple wavelength channels with a silicon nitride microring resonator chip.In our demonstration,we establish a fully connected graph between four users with six wavelength channels—saving half of which without sacrificing functionality and performance of the secure communication.A total asymptotic secure key rate of 1946.9 bps is obtained by performing the BBM92 protocol with the distributed state.The network topology of our method has great potential for developing a scalable quantum network with significantly minimized infrastructure requirements.
基金supported by Sichuan Science and Technology Program(Grant Nos.2023YFSY0061,2023YFSY0062,2024YFHZ0370,and 2024YFHZ0369)the National Natural Science Foundation of China(Grant Nos.92365106,62475039,and 62405046)Innovation Program for Quantum Science and Technology(Grant Nos.2024ZD0300800 and 2021ZD0300701).
文摘Quantum entanglement networks have garnered significant attention due to the inherent security provided by quantum physics.The networks aim to connect a multitude of users with a high secure key rate(SKR).Fully connected networks have been demonstrated using wavelength-division multiplexing architectures.However,the SKR of such networks remains challenging due to the limited brightness of quantum photon-pair sources and the loss introduced by cascaded filtering components.We present high-rate quantum entanglement networks that leverage a broadband quantum light source with high brightness and an industrygrade flexible wavelength-selective switching technique with uniform loss.By implementing the BBM92 protocol,we achieve an SKR of 28.19 kbps in a four-user network,representing a two-order-of-magnitude improvement over previous implementations.After transmission through a 40-km fiber spool,the SKR remains as high as 3.58 kbps and stays positive over distances up to 250 km.Furthermore,the flexibility of our scheme is illustrated by constructing a six-user network,achieving SKRs of 4.21 kbps and 0.45 kbps without and with a 40-km fiber spool,respectively.These results demonstrate a practical approach to enhancing the SKR and scalability in entanglement-based quantum networks,offering a feasible solution for deploying metropolitan and backbone quantum communication systems.
基金supported by the Sichuan Provincial Regional Innovation Cooperation Program(No.2023YFQ0013)the National Natural Science Foundation of China(No.62205093)+1 种基金the Sichuan Science and Technology Program(Nos.2021YFSY0063,2021YFSY0062,2021YFSY0064,2021YFSY0065,2021YFSY0066,2022YFSY0061,2022YFSY0062,and 2022YFSY0063)the Hainan Province Science and Technology Special Fund(No.ZDYF2023SHFZ135)。
文摘The reflection matrix optical coherence tomography(RM-OCT)method has made significant progress in extending imaging depth within scattering media.However,the current method of measuring the reflection matrix(RM)through uniform sampling results in relatively long data collection time.This study demonstrates that the RM in scattering media exhibits sparsity.Consequently,a compressed sensing(CS)-based technique for measuring the RM is proposed and applied to RM-OCT images.Experimental results show that this method requires less than 50%of the traditional sampling data to recover target information within scattering media,thereby significantly reducing data acquisition time.These findings not only expand the theory of the RM but also provide a more efficient measurement approach.This advancement opens up broader applications for CS techniques in RM-OCT and holds great potential for improving imaging efficiency in scattering media.
基金supported by the Sichuan Science and Technology Program(Nos.2022YFSY0061,2023YFSY0061,2022YFSY0062,2022YFSY0063,2023YFSY0058,and2023YFSY0060)the National Natural Science Foundation of China(Nos.62405046,62475039,and 92365106)+1 种基金the Innovation Program for Quantum Science and Technology(No.2021ZD0301702)the Tianfu Jiangxi Laboratory(No.TFJX-ZD-2024-002)。
文摘We report a broadband energy-time entangled photon-pair source based on a fiber-pigtailed periodically poled lithium niobate[PPLN]waveguide,designed for applications in the quantum secure network.Utilizing the spontaneous parametric down-conversion nonlinear optical process,the source generates entangled photon pairs within a wavelength range of64 nm in the telecom band at a pump wavelength of 770.3 nm.Photon pairs from eight paired International Telecommunication Union[ITU]channels are selected,and their correlation and entanglement properties are characterized.The measured coincidence counts of photon pairs from eight paired ITU channels are larger than 152.9 kHz when the coincidence-to-accidental ratios are greater than 260.Entanglement properties are measured through two-photon interference in the Franson interferometer,with all visibilities of interference curves exceeding 98.13%.Our demonstration provides a broadband energy-time entangled photon-pair source,contributing to the development of a large-scale quantum secure network.
基金Sichuan Science and Technology Program(2022YFSY0061,2022YFSY0062,2022YFSY0063,2023YFSY0058,2023NSFSC0048)Innovation Program for Quantum Science and Technology(2021ZD0301702)+2 种基金National Natural Science Foundation of China(12174222,62475039,62405046)Natural Science Foundation of Shandong Province(ZR2021ZD02)National Key Research and Development Program of China(2018YFA0306102,2022YFA1405900).
文摘The light–matter interface is an important building block for long-distance quantum networks.Towards a scalable quantum network with high-rate quantum information processing,it requires to develop integrated light–matter interfaces with broadband and multiplexing capacities.Here we demonstrate a light–matter interface at the telecom band in an integrated system.A five-spectral-channel atomic-frequency-comb photonic memory is prepared on a laser-written Er^(3+):LiNbO_(3)chip.The bandwidth of each channel is 4 GHz with a channel spacing of 15 GHz.The signal photons from time-bin entangled photon pairs at the telecom band are sent into the on-chip memory and recalled after a storage time of 152 ns.The entanglement-preserving nature of our integrated quantum interface is assessed by an input/output fidelity of>92%for all five spectral channels.Our light–matter interfaces constitute a notable step forward toward a high-rate quantum network involving integrated devices.
