Constructing large-scale quantum resources is an important foundation for further improving the efficiency and scalability of quantum communication.Here,we present an efficient extraction and stable control scheme of ...Constructing large-scale quantum resources is an important foundation for further improving the efficiency and scalability of quantum communication.Here,we present an efficient extraction and stable control scheme of 40 pairs of entangled sideband modes from the squeezed light by specially designing an optical parametric oscillator.Utilizing the low-loss optical frequency comb control technology and the local cross-correlation algorithm,we model and manage the efficient separation process of the entangled sideband modes facilitated by the optical filtering cavities,and a maximum entanglement level of 6.5 dB is achieved.The feasibility of large-capacity quantum dense coding based on these entangled sideband modes is proved experimentally,which is of great significance for optimizing the utilization of quantum resources,thereby contributing to the advancement of largecapacity quantum communication networks and enabling the realization of more secure and efficient quantum communication systems.展开更多
Quantum teleportation is a key primitive across a number of quantum information tasks and represents a fundamental ingredient for many quantum technologies. Channel capacity, other than the fidelity, becomes another f...Quantum teleportation is a key primitive across a number of quantum information tasks and represents a fundamental ingredient for many quantum technologies. Channel capacity, other than the fidelity, becomes another focus of quantum communication. Here, we present a 5-channel multiplexing continuous-variable quantum teleportation protocol in the optical frequency comb system, exploiting five-order entangled sideband modes.Because of the resonant electro-optical modulation(EOM) that is specifically designed, the fidelities of five channels are greater than 0.78, which are superior to the no-cloning limit of 2∕3. This work provides a feasible scheme for implementing efficient quantum information processing.展开更多
The detection of gravitational waves has ushered in a new era of observing the universe.Quantum resource advantages offer significant enhancements to the sensitivity of gravitational wave observatories.While squeezed ...The detection of gravitational waves has ushered in a new era of observing the universe.Quantum resource advantages offer significant enhancements to the sensitivity of gravitational wave observatories.While squeezed states for ground-based gravitational wave detection have received marked attention,the generation of squeezed states suitable for mid-to-low-frequency detection has remained unexplored.To address the gap in squeezed state optical fields at ultra-low frequencies,we report on the first direct observation of a squeezed vacuum field until Fourier frequency of 4 millihertz with the quantum noise reduction of up to 8.0 dB,by the employment of a multiple noise suppression scheme.Our work provides quantum resources for future gravitational wave observatories,facilitating the development of quantum precision measurement.展开更多
Quantum communication network scales point-to-point quantum communication protocols to more than two detached parties,which would permit a wide variety of quantum communication applications.Here,we demonstrate a fully...Quantum communication network scales point-to-point quantum communication protocols to more than two detached parties,which would permit a wide variety of quantum communication applications.Here,we demonstrate a fully-connected quantum communication network,exploiting three pairs of Einstein–Podolsky–Rosen(EPR)entangled sideband modes,with high degree entanglement of 8.0 dB,7.6 dB,and 7.2 dB.Each sideband modes from a squeezed field are spatially separated by demultiplexing operation,then recombining into new group according to network requirement.Each group of sideband modes are distributed to one of the parties via a single physical path,making sure each pair of parties build their own private communication links with high channel capacity better than any classical scheme.展开更多
We demonstrate a resolution enhancement scheme of radio-frequency signals by tailoring a phase-squeezed state.The echo radio-frequency signals collected by photonic radar give rise to displacements in the phase quadra...We demonstrate a resolution enhancement scheme of radio-frequency signals by tailoring a phase-squeezed state.The echo radio-frequency signals collected by photonic radar give rise to displacements in the phase quadrature of a probe laser and are estimated by the balanced homodyne detector.In contrast to the conventional coherent state,the noise variances for radio-frequency estimation with a squeezed state are reduced by approximately 6.9 dB.According to the Rayleigh criterion that defines the resolution limit,the minimum resolvable displacement Δa with a squeezed state is reduced to 45%compared to that with a coherent state,demonstrating the quantum advantage.The squeezing-enhanced technique has extensive applications for multitarget recognition and tracking in contemporary photonic radar systems.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.62225504,62027821,U22A6003,12304399,12174234,12274275,and 62375162)the Fundamental Research Program of Shanxi Province(Grant Nos.202303021212003,and 202303021224006).
文摘Constructing large-scale quantum resources is an important foundation for further improving the efficiency and scalability of quantum communication.Here,we present an efficient extraction and stable control scheme of 40 pairs of entangled sideband modes from the squeezed light by specially designing an optical parametric oscillator.Utilizing the low-loss optical frequency comb control technology and the local cross-correlation algorithm,we model and manage the efficient separation process of the entangled sideband modes facilitated by the optical filtering cavities,and a maximum entanglement level of 6.5 dB is achieved.The feasibility of large-capacity quantum dense coding based on these entangled sideband modes is proved experimentally,which is of great significance for optimizing the utilization of quantum resources,thereby contributing to the advancement of largecapacity quantum communication networks and enabling the realization of more secure and efficient quantum communication systems.
基金National Natural Science Foundation of China(62027821,11654002,11874250,12174234,62035015)National Key Research and Development Program of China(2020YFC2200402)+1 种基金Key Research and Development Program of Shanxi(201903D111001)Program for Sanjin Scholar of Shanxi Province。
文摘Quantum teleportation is a key primitive across a number of quantum information tasks and represents a fundamental ingredient for many quantum technologies. Channel capacity, other than the fidelity, becomes another focus of quantum communication. Here, we present a 5-channel multiplexing continuous-variable quantum teleportation protocol in the optical frequency comb system, exploiting five-order entangled sideband modes.Because of the resonant electro-optical modulation(EOM) that is specifically designed, the fidelities of five channels are greater than 0.78, which are superior to the no-cloning limit of 2∕3. This work provides a feasible scheme for implementing efficient quantum information processing.
基金sponsored by National Natural Science Foundation of China(NSFC)(Nos.62225504,62027821,U22A6003,62035015,12174234,12304399)National Key R&D Program of China(Grant No.2020YFC2200402)Fundamental Research Program of Shanxi Province(No.202303021212003,202303021224006).
文摘The detection of gravitational waves has ushered in a new era of observing the universe.Quantum resource advantages offer significant enhancements to the sensitivity of gravitational wave observatories.While squeezed states for ground-based gravitational wave detection have received marked attention,the generation of squeezed states suitable for mid-to-low-frequency detection has remained unexplored.To address the gap in squeezed state optical fields at ultra-low frequencies,we report on the first direct observation of a squeezed vacuum field until Fourier frequency of 4 millihertz with the quantum noise reduction of up to 8.0 dB,by the employment of a multiple noise suppression scheme.Our work provides quantum resources for future gravitational wave observatories,facilitating the development of quantum precision measurement.
基金the National Natural Science Foundation of China(NSFC)(Grant Nos.62225504,62027821,62035015,U22A6003,and 12174234)the National Key R&D Program of China(Grant No.2020YFC2200402)the Program for Sanjin Scholar of Shanxi Province.
文摘Quantum communication network scales point-to-point quantum communication protocols to more than two detached parties,which would permit a wide variety of quantum communication applications.Here,we demonstrate a fully-connected quantum communication network,exploiting three pairs of Einstein–Podolsky–Rosen(EPR)entangled sideband modes,with high degree entanglement of 8.0 dB,7.6 dB,and 7.2 dB.Each sideband modes from a squeezed field are spatially separated by demultiplexing operation,then recombining into new group according to network requirement.Each group of sideband modes are distributed to one of the parties via a single physical path,making sure each pair of parties build their own private communication links with high channel capacity better than any classical scheme.
基金supported by the National Natural Science Foundation of China(Nos.62225504,12274275,62027821,U22A6003,62035015,62375162,12304399,and 12174234)the Key R&D Program of Shanxi(No.202302150101015)the Fundamental Research Program of Shanxi Province(Nos.202303021212003 and 202303021224006).
文摘We demonstrate a resolution enhancement scheme of radio-frequency signals by tailoring a phase-squeezed state.The echo radio-frequency signals collected by photonic radar give rise to displacements in the phase quadrature of a probe laser and are estimated by the balanced homodyne detector.In contrast to the conventional coherent state,the noise variances for radio-frequency estimation with a squeezed state are reduced by approximately 6.9 dB.According to the Rayleigh criterion that defines the resolution limit,the minimum resolvable displacement Δa with a squeezed state is reduced to 45%compared to that with a coherent state,demonstrating the quantum advantage.The squeezing-enhanced technique has extensive applications for multitarget recognition and tracking in contemporary photonic radar systems.
