Acceleration sensing, an essential branch of quantum sensing, faces a fundamental trade-off between resolution and bandwidth. Here, we present a quantum-enhanced optomechanical accelerometer(QEOMA), simultaneously ach...Acceleration sensing, an essential branch of quantum sensing, faces a fundamental trade-off between resolution and bandwidth. Here, we present a quantum-enhanced optomechanical accelerometer(QEOMA), simultaneously achieving the improvement of the sensing resolution and bandwidth in contrast with a classical counterpart.By tailoring quantum squeezed light, the optomechanical cooperativity is significantly raised, extending the sensing bandwidth. Quantum squeezed light increases the equivalent Q value of the optomechanical accelerometer owing to the reduction of the mechanical damping rate, driving the resolution improvement at the resonance frequency. At off-resonance frequencies, the resolution improvement is attributed to the imprecision noise reduction. We obtain the measured noise power spectrum and inferred acceleration resolution for the(3,3),(4,4),(5,5), and(6,6) mechanical modes, respectively. The maximum quantum enhancement is measured for the(6,6) mechanical mode with a 38.4% resolution enhancement and 1.55-fold bandwidth broadening in contrast with a coherent probe. The proposed QEOMA shows significant potential for applications ranging from ultralight dark matter searches to inertial navigation of fast-moving objects.展开更多
The dominant technical noise of a free-running laser practically limits bright squeezed light generation,particularly within the MHz band.To overcome this,we develop a comprehensive theoretical model for nonclassical ...The dominant technical noise of a free-running laser practically limits bright squeezed light generation,particularly within the MHz band.To overcome this,we develop a comprehensive theoretical model for nonclassical power stabilization,and propose a novel bright squeezed light generation scheme incorporating hybrid power noise suppression.Our approach integrates broadband passive power stabilization with nonclassical active stabilization,extending the feedback bandwidth to MHz frequencies.This hybrid technique achieves an additional 9 dB technical noise suppression,establishing critical prerequisites for broadband bright squeezed light generation.Finally,a-5.5 dB bright squeezed light at 1 mW with kHz-MHz squeezing bandwidth was generated.The experimental results show excellent agreement with theoretical predictions,which represent we have comprehensively demonstrated a milliwatt-order bright squeezed light across kHz-MHz frequencies.Our work enables new quantum metrology applications and paves the way for next-generation quantum-enhanced technologies.展开更多
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
Atom-based sensing with optical readout is fundamentally limited by photon shot noise.Squeezed light can effectively suppress this noise of optical readout,thereby enabling measurement sensitivities beyond the standar...Atom-based sensing with optical readout is fundamentally limited by photon shot noise.Squeezed light can effectively suppress this noise of optical readout,thereby enabling measurement sensitivities beyond the standard quantum limit,but their application in light–atom hybrid systems is often hindered by absorption losses of atomic medium.Here,we demonstrate the first realization of electromagnetically induced transparency spectrum in a Rydberg-atom system using a squeezed probe field that surpasses the photon shot noise limit.Our theoretical model identifies atomic transit and absorption-induced losses as the primary factors limiting squeezing preservation.Experimentally,we engineer the atomic ensemble as a medium with tunable transmittance by employing Doppler-matched velocity-selective excitation to suppress absorption,achieving a squeezing transmission of 90.4%for-1.7 dB squeezed light through a cesium vapor cell.This work is a critical step towards quantum-enhanced Rydberg atom sensors.展开更多
Squeezed states belong to the most prominent non-classical resources.They have compelling applications in precise measurement, quantum computation, and detection.Here, we report on the direct measurement of 13.8 d B s...Squeezed states belong to the most prominent non-classical resources.They have compelling applications in precise measurement, quantum computation, and detection.Here, we report on the direct measurement of 13.8 d B squeezed vacuum states by improving the interference efficiency and gain of balanced homodyne detection.By employing an auxiliary laser beam, the homodyne visibility is increased to 99.8%.The equivalent loss of the electronic noise is reduced to 0.05% by integrating a junction field-effect transistor(JFET) buffering input and another JFET bootstrap structure in the balanced homodyne detector.展开更多
Background:Cystic echinococcosis is one of the most severe helminth zoonosis with a drastic impact on human health and livestock industry.Investigating optimal control strategy and assessing the crucial factors are es...Background:Cystic echinococcosis is one of the most severe helminth zoonosis with a drastic impact on human health and livestock industry.Investigating optimal control strategy and assessing the crucial factors are essential for developing countermeasures to mitigate this disease.Methods:Two compartment models were formulated to study the dynamics of cystic echinococcosis transmission,to evaluate the effectiveness of various control measures,and to find the optimal control strategy.Sensitive analyses were conducted by obtaining PRCCs and contour plot was used to evaluate the effect of key parameters on the basic reproduction number.Based on forward-backward sweep method,numerical simulations were employed to investigate effects of key factors on the transmission of cystic echinococcosis and to obtain the optimal control strategy.Results:The food resources of stray dog and invalid sheep vaccination rate,which are always neglected,were significant to the transmission and control of cystic echinococcosis.Numerical simulations suggest that,the implementation of optimal control strategy can significantly reduce the infections.Improving the cost of health education and domestic dog deworming could not decrease human infections.Conclusions:Our study showed that only a long-term use of the optimal control measures can eliminate the disease.Meanwhile,during the intervention,sheep vaccination and stray dogs disposing should be emphasized ahead of domestic dogs deworming to minimize the control cost.Simultaneously reducing other wild intermediate hosts and strengthening the sheep vaccination as well as disposing the stray dogs would be most effective.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
Our previous work had proved pump field noise coupling in the seed field injected optical parametric amplifier(OPA)at a certain analysis frequency.Inspired by this noise coupling mechanism,the frequency dependent sque...Our previous work had proved pump field noise coupling in the seed field injected optical parametric amplifier(OPA)at a certain analysis frequency.Inspired by this noise coupling mechanism,the frequency dependent squeezing factor due to excess pump noise was experimentally demonstrated.Apart from a reduced squeezing level with an increased noise,the results also prove that a broadband squeezing noise spectrum is not frequency dependent on the amplitude modulated pump field,but limited by the bandwidth of the amplitude modulator and OPA resonator,and the effective measurement is carried out in the frequency range of 2–10 MHz.It provides a guidance to design a broader-bandwidth,higher-level bright squeezed light.展开更多
A quantum sensor network with multipartite entanglement offers a sensitivity advantage in optical phase estimation over the classical scheme.To tackle richer sensing problems,we construct a distributed sensor network ...A quantum sensor network with multipartite entanglement offers a sensitivity advantage in optical phase estimation over the classical scheme.To tackle richer sensing problems,we construct a distributed sensor network with four nodes via four partite entanglements,unveil the estimation of the higher order derivative of radiofrequency signal phase,and unlock the potential of quantum target ranging and space positioning.Taking phased-array radar as an example,we demonstrate the optimal quantum advantages for space positioning and target ranging missions.Without doubt,the demonstration that endows innovative physical conception opens up widespread application of quantum sensor networks.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
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
基金National Natural Science Foundation of China(62225504,12274275,62027821,U22A6003,62375162,12304399,12174234)Key R&D Program of Shanxi(202302150101004).
文摘Acceleration sensing, an essential branch of quantum sensing, faces a fundamental trade-off between resolution and bandwidth. Here, we present a quantum-enhanced optomechanical accelerometer(QEOMA), simultaneously achieving the improvement of the sensing resolution and bandwidth in contrast with a classical counterpart.By tailoring quantum squeezed light, the optomechanical cooperativity is significantly raised, extending the sensing bandwidth. Quantum squeezed light increases the equivalent Q value of the optomechanical accelerometer owing to the reduction of the mechanical damping rate, driving the resolution improvement at the resonance frequency. At off-resonance frequencies, the resolution improvement is attributed to the imprecision noise reduction. We obtain the measured noise power spectrum and inferred acceleration resolution for the(3,3),(4,4),(5,5), and(6,6) mechanical modes, respectively. The maximum quantum enhancement is measured for the(6,6) mechanical mode with a 38.4% resolution enhancement and 1.55-fold bandwidth broadening in contrast with a coherent probe. The proposed QEOMA shows significant potential for applications ranging from ultralight dark matter searches to inertial navigation of fast-moving objects.
基金sponsored by the National Natural Science Foundation of China(NSFC)(Grant Nos.62225504,U22A6003,62027821,and 62375162)the National Key Research and Development Program of China(No.2024YFF0726401).
文摘The dominant technical noise of a free-running laser practically limits bright squeezed light generation,particularly within the MHz band.To overcome this,we develop a comprehensive theoretical model for nonclassical power stabilization,and propose a novel bright squeezed light generation scheme incorporating hybrid power noise suppression.Our approach integrates broadband passive power stabilization with nonclassical active stabilization,extending the feedback bandwidth to MHz frequencies.This hybrid technique achieves an additional 9 dB technical noise suppression,establishing critical prerequisites for broadband bright squeezed light generation.Finally,a-5.5 dB bright squeezed light at 1 mW with kHz-MHz squeezing bandwidth was generated.The experimental results show excellent agreement with theoretical predictions,which represent we have comprehensively demonstrated a milliwatt-order bright squeezed light across kHz-MHz frequencies.Our work enables new quantum metrology applications and paves the way for next-generation quantum-enhanced technologies.
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funded by the National Key R&D Program of China(Grant no.2022YFA1404003)the National Natural Science Foundation of China(Grants T2495252,12104279)Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302100).
文摘Atom-based sensing with optical readout is fundamentally limited by photon shot noise.Squeezed light can effectively suppress this noise of optical readout,thereby enabling measurement sensitivities beyond the standard quantum limit,but their application in light–atom hybrid systems is often hindered by absorption losses of atomic medium.Here,we demonstrate the first realization of electromagnetically induced transparency spectrum in a Rydberg-atom system using a squeezed probe field that surpasses the photon shot noise limit.Our theoretical model identifies atomic transit and absorption-induced losses as the primary factors limiting squeezing preservation.Experimentally,we engineer the atomic ensemble as a medium with tunable transmittance by employing Doppler-matched velocity-selective excitation to suppress absorption,achieving a squeezing transmission of 90.4%for-1.7 dB squeezed light through a cesium vapor cell.This work is a critical step towards quantum-enhanced Rydberg atom sensors.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.11654002,61575114,11874250,and 11804207)National Key Research and Development Program of China(No.2016YFA0301401)+2 种基金Program for Sanjin Scholar of Shanxi ProvinceProgram for Outstanding Innovative Teams of Higher Learning Institutions of ShanxiFund for Shanxi “1331 Project”Key Subjects Construction
文摘Squeezed states belong to the most prominent non-classical resources.They have compelling applications in precise measurement, quantum computation, and detection.Here, we report on the direct measurement of 13.8 d B squeezed vacuum states by improving the interference efficiency and gain of balanced homodyne detection.By employing an auxiliary laser beam, the homodyne visibility is increased to 99.8%.The equivalent loss of the electronic noise is reduced to 0.05% by integrating a junction field-effect transistor(JFET) buffering input and another JFET bootstrap structure in the balanced homodyne detector.
基金supported by National Natural Science Foundation of P.R.China(No.12071068,11671072)Natural Science Foundation of Jilin Province,P.R.China and partially supported by NSERC of Canada and York Research Chair Program.
文摘Background:Cystic echinococcosis is one of the most severe helminth zoonosis with a drastic impact on human health and livestock industry.Investigating optimal control strategy and assessing the crucial factors are essential for developing countermeasures to mitigate this disease.Methods:Two compartment models were formulated to study the dynamics of cystic echinococcosis transmission,to evaluate the effectiveness of various control measures,and to find the optimal control strategy.Sensitive analyses were conducted by obtaining PRCCs and contour plot was used to evaluate the effect of key parameters on the basic reproduction number.Based on forward-backward sweep method,numerical simulations were employed to investigate effects of key factors on the transmission of cystic echinococcosis and to obtain the optimal control strategy.Results:The food resources of stray dog and invalid sheep vaccination rate,which are always neglected,were significant to the transmission and control of cystic echinococcosis.Numerical simulations suggest that,the implementation of optimal control strategy can significantly reduce the infections.Improving the cost of health education and domestic dog deworming could not decrease human infections.Conclusions:Our study showed that only a long-term use of the optimal control measures can eliminate the disease.Meanwhile,during the intervention,sheep vaccination and stray dogs disposing should be emphasized ahead of domestic dogs deworming to minimize the control cost.Simultaneously reducing other wild intermediate hosts and strengthening the sheep vaccination as well as disposing the stray dogs would be most effective.
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the National Natural Science Foundation of China(NSFC)(Nos.62027821,11654002,11874250,and 11804207)the National KeyResearch and Development Program of China(No.2020YFC2200402)+3 种基金the KeyResearch and Development Projects of Shanxi Province(No.201903D111001)the Program for Sanjin Scholar of Shanxi ProvincetheProgram for Outstanding Innovative Teams of Higher LearningInstitutions of Shanxithe Fund for Shanxi“1331 Project”KeySubjects Construction。
文摘Our previous work had proved pump field noise coupling in the seed field injected optical parametric amplifier(OPA)at a certain analysis frequency.Inspired by this noise coupling mechanism,the frequency dependent squeezing factor due to excess pump noise was experimentally demonstrated.Apart from a reduced squeezing level with an increased noise,the results also prove that a broadband squeezing noise spectrum is not frequency dependent on the amplitude modulated pump field,but limited by the bandwidth of the amplitude modulator and OPA resonator,and the effective measurement is carried out in the frequency range of 2–10 MHz.It provides a guidance to design a broader-bandwidth,higher-level bright squeezed light.
基金National Natural Science Foundation of China(62225504,62027821,11874250,12174234,12274275,62035015)National Key Research and Development Program of China(2020YFC2200402)+1 种基金Key R&D Program of Shanxi(202102150101003)Program for Sanjin Scholar of Shanxi Province。
文摘A quantum sensor network with multipartite entanglement offers a sensitivity advantage in optical phase estimation over the classical scheme.To tackle richer sensing problems,we construct a distributed sensor network with four nodes via four partite entanglements,unveil the estimation of the higher order derivative of radiofrequency signal phase,and unlock the potential of quantum target ranging and space positioning.Taking phased-array radar as an example,we demonstrate the optimal quantum advantages for space positioning and target ranging missions.Without doubt,the demonstration that endows innovative physical conception opens up widespread application of quantum sensor networks.
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.
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.
