A team of researchers from the Department of Biomedical Engineering at Stanford University has announced the clinical validation of a flexible wearable biosensor that enables real-time monitoring of key metabolic biom...A team of researchers from the Department of Biomedical Engineering at Stanford University has announced the clinical validation of a flexible wearable biosensor that enables real-time monitoring of key metabolic biomarkers.The device,which integrates microfluidic technology,electrochemical sensing,and biocompatible materials,represents a significant advancement in point-of-care diagnostics and personalized medicine.展开更多
The Global Navigation Satellite System(GNSS)has been widely adopted in numerous fields,including intelligent transportation,remote sensing,and aeronautical and astronautical engineering.As new navigation approaches,te...The Global Navigation Satellite System(GNSS)has been widely adopted in numerous fields,including intelligent transportation,remote sensing,and aeronautical and astronautical engineering.As new navigation approaches,technologies,and applications continue to emerge,they attract significant global attention.Ensuring reliable positioning solutions with high accuracy,strong anti-interference capabilities,high availability and low integrity risks has become increasingly critical.展开更多
The transportable optical clock can be deployed in various transportation vehicles,including aviation,aerospace,maritime,and land-based vehicles;provides remote time standards for geophysical monitoring and distribute...The transportable optical clock can be deployed in various transportation vehicles,including aviation,aerospace,maritime,and land-based vehicles;provides remote time standards for geophysical monitoring and distributed coherent sensing;and promotes the unmanned and lightweight development of global time network synchronization.However,the current transportable version of laboratory optical clocks is still limited by factors such as environmental sensitivity,manual maintenance requirements,and high cost.Here we report a single-person portable optical frequency standard using the recently proposed atomic-filter-based laser“Voigt laser”as the local oscillator.It is worth mentioning that due to the inherent characteristics of Voigt lasers,the Voigt optical frequency standard can maintain turn-key functionality under harsh environmental impacts without any manual maintenance requirement.In our experiment,conducted over a duration of 12 min,we subjected the laser diode to multiple temperature shocks,resulting in a cumulative temperature fluctuation of 15℃.Following each temperature shock event,the Voigt optical frequency standard automatically relocked and restored the frequency output.Therefore,this demonstration marks a significant technological breakthrough in automatic quantum devices and might herald the arrival of fully automated time network systems.展开更多
Nature 643,669-674(2025)Photon avalanche is a distinctive optical nonlinear phe-nomenon observed in lanthanide-doped nanocrystals,which holds great potential for super-resolution imaging,ultrasensitive optical sensing...Nature 643,669-674(2025)Photon avalanche is a distinctive optical nonlinear phe-nomenon observed in lanthanide-doped nanocrystals,which holds great potential for super-resolution imaging,ultrasensitive optical sensing,and multiphysics field detec-tion.However,further enhancement of nonlinearity in photon avalanche nanomaterials remains challenging.展开更多
Two-dimensional transition metal dichalcogenides are of great interest for second harmonic generation due to their large second-order susceptibilityx(2),atomically thin structure,and relaxed phase-matching conditions....Two-dimensional transition metal dichalcogenides are of great interest for second harmonic generation due to their large second-order susceptibilityx(2),atomically thin structure,and relaxed phase-matching conditions.Such materials are also promising candidates for miniaturizing nonlinear optical devices for versatile applications in photon manipulation,quantum emission and sensing,and nanophotonic circuits.However,their strong sec-ond harmonic response is limited by nanometer-scale light-matter interaction and material impurities.Although there is considerable work toward engineering these materials for enhancing their nonlinear responses,all-optical methods are still in the exploration stages.We incorporate,to the best of our knowledge,the first experimental demonstration of feedback-based wavefront shaping techniques in atomically thin media to reveal and enhance the weak second harmonic generation of monolayer WS_(2).Phase tuning of the incident wavefront leads to the increase in the intensity of the second harmonic generated in the target regions up to an order of magnitude.We enhance the local nonlinear signal conversion from monolayer WS_(2)up to 41 x using phase-only modulation.Furthermore,by introducing a shift in the transverse phase structure,we achieve observable second harmonic generation at the destructively interfering grain boundaries of polycrystalline monolayers.This method allows for all-optical tuning of transition metal dichalcogenides'nonlinear responses,opening up possibilities for dynamic signal routing and on-demand enhancement in nanoscale photonic systems.展开更多
文摘A team of researchers from the Department of Biomedical Engineering at Stanford University has announced the clinical validation of a flexible wearable biosensor that enables real-time monitoring of key metabolic biomarkers.The device,which integrates microfluidic technology,electrochemical sensing,and biocompatible materials,represents a significant advancement in point-of-care diagnostics and personalized medicine.
文摘The Global Navigation Satellite System(GNSS)has been widely adopted in numerous fields,including intelligent transportation,remote sensing,and aeronautical and astronautical engineering.As new navigation approaches,technologies,and applications continue to emerge,they attract significant global attention.Ensuring reliable positioning solutions with high accuracy,strong anti-interference capabilities,high availability and low integrity risks has become increasingly critical.
基金Innovation Program for Quantum Science and Technology(2021ZD0303200)National Natural Science Foundation of China(62405007,624B2010)+1 种基金China Postdoctoral Science Foundation(BX2021020)Wenzhou Major Science and Technology Innovation Key Project(ZG2020046)。
文摘The transportable optical clock can be deployed in various transportation vehicles,including aviation,aerospace,maritime,and land-based vehicles;provides remote time standards for geophysical monitoring and distributed coherent sensing;and promotes the unmanned and lightweight development of global time network synchronization.However,the current transportable version of laboratory optical clocks is still limited by factors such as environmental sensitivity,manual maintenance requirements,and high cost.Here we report a single-person portable optical frequency standard using the recently proposed atomic-filter-based laser“Voigt laser”as the local oscillator.It is worth mentioning that due to the inherent characteristics of Voigt lasers,the Voigt optical frequency standard can maintain turn-key functionality under harsh environmental impacts without any manual maintenance requirement.In our experiment,conducted over a duration of 12 min,we subjected the laser diode to multiple temperature shocks,resulting in a cumulative temperature fluctuation of 15℃.Following each temperature shock event,the Voigt optical frequency standard automatically relocked and restored the frequency output.Therefore,this demonstration marks a significant technological breakthrough in automatic quantum devices and might herald the arrival of fully automated time network systems.
文摘Nature 643,669-674(2025)Photon avalanche is a distinctive optical nonlinear phe-nomenon observed in lanthanide-doped nanocrystals,which holds great potential for super-resolution imaging,ultrasensitive optical sensing,and multiphysics field detec-tion.However,further enhancement of nonlinearity in photon avalanche nanomaterials remains challenging.
基金Gordon and Betty Moore FoundationU.S.Department of Energy(DE-SC0024676)+2 种基金National Geospatial-Intelligence Agency(HM04762010012)U.S.Department of Energy(DE-SC0023148)Air Force Office of Scientific Research(FA9550-23-1-0325).
文摘Two-dimensional transition metal dichalcogenides are of great interest for second harmonic generation due to their large second-order susceptibilityx(2),atomically thin structure,and relaxed phase-matching conditions.Such materials are also promising candidates for miniaturizing nonlinear optical devices for versatile applications in photon manipulation,quantum emission and sensing,and nanophotonic circuits.However,their strong sec-ond harmonic response is limited by nanometer-scale light-matter interaction and material impurities.Although there is considerable work toward engineering these materials for enhancing their nonlinear responses,all-optical methods are still in the exploration stages.We incorporate,to the best of our knowledge,the first experimental demonstration of feedback-based wavefront shaping techniques in atomically thin media to reveal and enhance the weak second harmonic generation of monolayer WS_(2).Phase tuning of the incident wavefront leads to the increase in the intensity of the second harmonic generated in the target regions up to an order of magnitude.We enhance the local nonlinear signal conversion from monolayer WS_(2)up to 41 x using phase-only modulation.Furthermore,by introducing a shift in the transverse phase structure,we achieve observable second harmonic generation at the destructively interfering grain boundaries of polycrystalline monolayers.This method allows for all-optical tuning of transition metal dichalcogenides'nonlinear responses,opening up possibilities for dynamic signal routing and on-demand enhancement in nanoscale photonic systems.
