Integrated circuit(IC)industry has fully considered the fact that the Moore’s Law is slowing down or ending.Alternative solutions are highly and urgently desired to break the physical size limits in the More-than-Moo...Integrated circuit(IC)industry has fully considered the fact that the Moore’s Law is slowing down or ending.Alternative solutions are highly and urgently desired to break the physical size limits in the More-than-Moore era.Integrated silicon photonics technology exhibits distinguished potential to achieve faster operation speed,less power dissipation,and lower cost in IC industry,because their COMS compatibility,fast response,and high monolithic integration capability.Particularly,compared with other on-chip resonators(e.g.microrings,2D photonic crystal cavities)silicon-on-insulator(SOI)-based photonic crystal nanobeam cavity(PCNC)has emerged as a promising platform for on-chip integration,due to their attractive properties of ultra-high Q/V,ultra-compact footprints and convenient integration with silicon bus-waveguides.In this paper,we present a comprehensive review on recent progress of on-chip PCNC devices for lasing,modulation,switching/filting and label-free sensing,etc.展开更多
Traditional optical communication systems employ bulky laser arrays that lack coherence and are prone to severe frequency drift.Dissipative Kerr soliton microcombs offer numerous evenly spaced optical carriers with a ...Traditional optical communication systems employ bulky laser arrays that lack coherence and are prone to severe frequency drift.Dissipative Kerr soliton microcombs offer numerous evenly spaced optical carriers with a high optical signal-to-noise ratio(OSNR)and coherence in chip-scale packages,potentially addressing the limitations of traditional wavelength division multiplexing(WDM)sources.However,soliton microcombs exhibit inhomogeneous OSNR and linewidth distributions across the spectra,leading to variable communication performance under uniform modulation schemes.Here,we demonstrate,for the first time,to our knowledge,the application of adaptive modulation and bandwidth allocation strategies in optical frequency comb(OFC)communication systems to optimize modulation schemes based on OSNR,linewidth,and channel bandwidth,thereby maximizing capacity.Experimental verification demonstrates that the method enhances spectral efficiency from 1.6 to2.31 bit·s^(-1)·Hz^(-1),signifying a 44.58%augmentation.Using a single-soliton microcomb as the light source,we achieve a maximum communication capacity of 10.68 Tbps after 40 km of transmission in the C-band,with the maximum single-channel capacity reaching 432 Gbps.The projected combined transmission capacity for the C-and L-bands could surpass 20 Tbps.The proposed strategies demonstrate promising potential of utilizing soliton microcombs as future light sources in next-generation optical communication.展开更多
All-dielectric metamaterials have emerged as a promising platform for low-loss and highly efficient terahertz devices. However, existing fabrication methods have difficulty in achieving a good balance between precisio...All-dielectric metamaterials have emerged as a promising platform for low-loss and highly efficient terahertz devices. However, existing fabrication methods have difficulty in achieving a good balance between precision and cost. Here, inspired by the nano-template-assisted self-assembly method, we develop a micro-templateassisted self-assembly(MTAS) method to prepare large-scale, high-precision, and flexible ceramic microsphere all-dielectric metamaterials with an area exceeding 900 cm × 900 cm. Free from organic solvents, vacuum, and complex equipment, the MTAS method ensures low-cost and environmentally friendly fabrication. The ceramic microsphere resonators can be readily assembled into nearly arbitrary arrangements and complex aggregates, such as dimers, trimers, quadrumers, and chains. Finally, using the heat-shrinkable substrate and dipole coupling effect, a broadband reflector with a bandwidth of 0.15 THz and a reflection of up to 95% is demonstrated.This work provides a versatile and powerful platform for terahertz all-dielectric metamaterials, with potential to be applied in a wide variety of high-efficiency terahertz devices.展开更多
The ability to sense dynamic biochemical reactions and material processes is particularly crucial for a wide range of applications,such as early-stage disease diagnosis and biomedicine development.Optical microcavitie...The ability to sense dynamic biochemical reactions and material processes is particularly crucial for a wide range of applications,such as early-stage disease diagnosis and biomedicine development.Optical microcavities-based label-free biosensors are renowned for ultrahigh sensitivities,and the detection limit has reached a single nanoparticle/molecule level.In particular,a microbubble resonator combined with an ultrahigh quality factor(Q)and inherent microfluidic channel is an intriguing platform for optical biosensing in an aqueous environment.In this work,an ultrahigh Q microbubble resonator-based sensor is used to characterize dynamic phase transition of a thermosensitive hydrogel.Experimentally,by monitoring resonance wavelength shift and linewidth broadening,we(for the first time to our knowledge)reveal that the refractive index is increased and light scattering is enhanced simultaneously during the hydrogel hydrophobic transition process.The platform demonstrated here paves the way to microfluidical biochemical dynamic detection and can be further adapted to investigating single-molecule kinetics.展开更多
Whispering gallery mode(WGM)microcavities provide increasing opportunities for precision measurement due to their ultrahigh sensitivity,compact size,and fast response.However,the conventional WGM sensors rely on monit...Whispering gallery mode(WGM)microcavities provide increasing opportunities for precision measurement due to their ultrahigh sensitivity,compact size,and fast response.However,the conventional WGM sensors rely on monitoring the changes of a single mode,and the abundant sensing information in WGM transmission spectra has not been fully utilized.Here,empowered by machine learning(ML),we propose and demonstrate an ergodic spectra sensing method in an optofluidic microcavity for high-precision pressure measurement.The developed ML method realizes the analysis of the full features of optical spectra.The prediction accuracy of 99.97%is obtained with the average error as low as 0.32 kPa in the pressure range of 100 kPa via the training and testing stages.We further achieve the real-time readout of arbitrary unknown pressure within the range of measurement,and a prediction accuracy of 99.51%is obtained.Moreover,we demonstrate that the ergodic spectra sensing accuracy is∼11.5%higher than that of simply extracting resonating modes’wavelength.With the high sensitivity and prediction accuracy,this work opens up a new avenue for integrated intelligent optical sensing.展开更多
Optical microcavities have the ability to confne photons in small mode volumes for long periods of time,greatly enhancing light-matter interactions,and have become one of the research hotspots in international academi...Optical microcavities have the ability to confne photons in small mode volumes for long periods of time,greatly enhancing light-matter interactions,and have become one of the research hotspots in international academia.In recent years,sensing applications in complex environments have inspired the development of multimode optical microcavity sensors.These multimode sensors can be used not only for multi-parameter detection but also to improve measurement precision.In this review,we introduce multimode sensing methods based on optical microcavities and present an overview of the multimode single/multi-parameter optical microcavities sensors.Expected further research activities are also put forward.展开更多
Optical trapping techniques are of great interest since they have the advantage of enabling the direct handling of nanoparticles. Among various optical trapping systems, photonic crystal nanobeam cavities have attract...Optical trapping techniques are of great interest since they have the advantage of enabling the direct handling of nanoparticles. Among various optical trapping systems, photonic crystal nanobeam cavities have attracted great attention for integrated on-chip trapping and manipulation. However, optical trapping with high efficiency and low input power is still a big challenge in nanobeam cavities because most of the light energy is confined within the solid dielectric region. To this end, by incorporating a nanoslotted structure into an ultracompact one- dimensional photonic crystal nanobeam cavity structure, we design a promising on-chip device with ultralarge trapping potential depth to enhance the optical trapping characteristic of the cavity. In this work, we first provide a systematic analysis of the optical trapping force for an airborne polystyrene （PS） nanoparticle trapped in a cavity model. Then, to validate the theoretical analysis, the numerical simulation proof is demonstrated in detail by using the three-dimensional finite element method. For trapping a PS nanoparticle of 10 nm radius within the air-slot, a maximum trapping force as high as 8.28 nN/mW and a depth of trapping potential as large as 1.15 × 105 kBTmW-1 are obtained, where kB is the Boltzmann constant and T is the system temperature. We estimate a lateral trapping stiffness of 167.17 pN. nm-1 . mW-1 for a 10 nm radius PS nanoparticle along the cavity x-axis, more than two orders of magnitude higher than previously demonstrated on-chip, near field traps. Moreover, the threshold power for stable trapping as low as 0.087 μW is achieved. In addition, trapping of a single 25 nm radius PS nanoparticle causes a 0.6 nm redshift in peak wavelength. Thus, the proposed cavity device can be used to detect single nanoparticle trapping by monitoring the resonant peak wavelength shift. We believe that the architecture with features of an ultracompact footprint, high integrahility with optical waveguides/cir- cuits, and efficient trapping demonstrated here will provide a promising candidate for developing a lab-on-a-chip device with versatile functionalities.展开更多
基金This work was supported by the National Key R&D Program of China(Grant No.2016YFA0301302 and No.2018YFB 2200401)the National Natural Science Foundation of China(Grant Nos.11974058,11825402,11654003,61435001)+4 种基金Beijing Academy of Quantum Information Sciences(Grant No.Y18G20)Key R&D Program of Guangdong Province(Grant No.2018B030329001)Beijing Nova Program(Grant No.Z201100006820125)from Beijing Municipal ScienceTechnology Commission,Fundamental Research Funds for the Central Universities(Grant No.2018XKJC05)the High Performance Computing Platform of Peking University.
文摘Integrated circuit(IC)industry has fully considered the fact that the Moore’s Law is slowing down or ending.Alternative solutions are highly and urgently desired to break the physical size limits in the More-than-Moore era.Integrated silicon photonics technology exhibits distinguished potential to achieve faster operation speed,less power dissipation,and lower cost in IC industry,because their COMS compatibility,fast response,and high monolithic integration capability.Particularly,compared with other on-chip resonators(e.g.microrings,2D photonic crystal cavities)silicon-on-insulator(SOI)-based photonic crystal nanobeam cavity(PCNC)has emerged as a promising platform for on-chip integration,due to their attractive properties of ultra-high Q/V,ultra-compact footprints and convenient integration with silicon bus-waveguides.In this paper,we present a comprehensive review on recent progress of on-chip PCNC devices for lasing,modulation,switching/filting and label-free sensing,etc.
基金Beijing Municipal Natural Science Foundation(Z210004)National Key Research and Development Program of China(SQ2023YFB2805600)+6 种基金State Key Laboratory of Information Photonics and Optical Communications,BUPT,China(IPOC2021ZT01)Beijing Nova Program from Beijing Municipal Science and Technology Commission(20230484433)Fundamental Research Funds for the Central Universities(2023PY08)Beijing University of Posts and Telecommunications(530224024)National Natural Science Foundation of China(62271517)Basic and Applied Basic Research Foundation of Guangdong Province(2023B1515020003)State Key Laboratory of Advanced Optical Communication Systems and Networks of China(2024GZKF19)。
文摘Traditional optical communication systems employ bulky laser arrays that lack coherence and are prone to severe frequency drift.Dissipative Kerr soliton microcombs offer numerous evenly spaced optical carriers with a high optical signal-to-noise ratio(OSNR)and coherence in chip-scale packages,potentially addressing the limitations of traditional wavelength division multiplexing(WDM)sources.However,soliton microcombs exhibit inhomogeneous OSNR and linewidth distributions across the spectra,leading to variable communication performance under uniform modulation schemes.Here,we demonstrate,for the first time,to our knowledge,the application of adaptive modulation and bandwidth allocation strategies in optical frequency comb(OFC)communication systems to optimize modulation schemes based on OSNR,linewidth,and channel bandwidth,thereby maximizing capacity.Experimental verification demonstrates that the method enhances spectral efficiency from 1.6 to2.31 bit·s^(-1)·Hz^(-1),signifying a 44.58%augmentation.Using a single-soliton microcomb as the light source,we achieve a maximum communication capacity of 10.68 Tbps after 40 km of transmission in the C-band,with the maximum single-channel capacity reaching 432 Gbps.The projected combined transmission capacity for the C-and L-bands could surpass 20 Tbps.The proposed strategies demonstrate promising potential of utilizing soliton microcombs as future light sources in next-generation optical communication.
基金National Natural Science Foundation of China(NSFC)(61774020,51502179)Department of Education of Hebei Province(QN2016156)+3 种基金Natural Science Foundation of Hebei Province(E2017210096)Fund of IPOC Beijing University of Posts and Telecommunications(BUPT)(IPOC2017ZT06)Fundamental Research Funds for the Central Universities(2018XKJC05)General Financial Grant from the China Postdoctoral Science Foundation(2017M620693)
文摘All-dielectric metamaterials have emerged as a promising platform for low-loss and highly efficient terahertz devices. However, existing fabrication methods have difficulty in achieving a good balance between precision and cost. Here, inspired by the nano-template-assisted self-assembly method, we develop a micro-templateassisted self-assembly(MTAS) method to prepare large-scale, high-precision, and flexible ceramic microsphere all-dielectric metamaterials with an area exceeding 900 cm × 900 cm. Free from organic solvents, vacuum, and complex equipment, the MTAS method ensures low-cost and environmentally friendly fabrication. The ceramic microsphere resonators can be readily assembled into nearly arbitrary arrangements and complex aggregates, such as dimers, trimers, quadrumers, and chains. Finally, using the heat-shrinkable substrate and dipole coupling effect, a broadband reflector with a bandwidth of 0.15 THz and a reflection of up to 95% is demonstrated.This work provides a versatile and powerful platform for terahertz all-dielectric metamaterials, with potential to be applied in a wide variety of high-efficiency terahertz devices.
基金National Key Research and Development Program of China(2018YFB2200401,2016YFA0301302)National Natural Science Foundation of China(11654003,11825402,11974058,61435001)+2 种基金Key R&D Program of Guangdong Province(2018B030329001)Fundamental Research Funds for the Central Universities(2018XKJC05)State Key Laboratory of Information Photonics and Optical Communications(IPOC2019ZT03)。
文摘The ability to sense dynamic biochemical reactions and material processes is particularly crucial for a wide range of applications,such as early-stage disease diagnosis and biomedicine development.Optical microcavities-based label-free biosensors are renowned for ultrahigh sensitivities,and the detection limit has reached a single nanoparticle/molecule level.In particular,a microbubble resonator combined with an ultrahigh quality factor(Q)and inherent microfluidic channel is an intriguing platform for optical biosensing in an aqueous environment.In this work,an ultrahigh Q microbubble resonator-based sensor is used to characterize dynamic phase transition of a thermosensitive hydrogel.Experimentally,by monitoring resonance wavelength shift and linewidth broadening,we(for the first time to our knowledge)reveal that the refractive index is increased and light scattering is enhanced simultaneously during the hydrogel hydrophobic transition process.The platform demonstrated here paves the way to microfluidical biochemical dynamic detection and can be further adapted to investigating single-molecule kinetics.
基金National Natural Science Foundation of China(11974058,62005231,62131002)A3 Foresight Program of NSFC(62061146002)+3 种基金Beijing Nova Program from Beijing Municipal Science and Technology Commission(Z201100006820125)Beijing Municipal Natural Science Foundation(Z210004)State Key Laboratory of Information Photonics and Optical Communications,BUPT,China(IPOC2021ZT01)BUPT Excellent Ph.D.Students Foundation(CX2022114).
文摘Whispering gallery mode(WGM)microcavities provide increasing opportunities for precision measurement due to their ultrahigh sensitivity,compact size,and fast response.However,the conventional WGM sensors rely on monitoring the changes of a single mode,and the abundant sensing information in WGM transmission spectra has not been fully utilized.Here,empowered by machine learning(ML),we propose and demonstrate an ergodic spectra sensing method in an optofluidic microcavity for high-precision pressure measurement.The developed ML method realizes the analysis of the full features of optical spectra.The prediction accuracy of 99.97%is obtained with the average error as low as 0.32 kPa in the pressure range of 100 kPa via the training and testing stages.We further achieve the real-time readout of arbitrary unknown pressure within the range of measurement,and a prediction accuracy of 99.51%is obtained.Moreover,we demonstrate that the ergodic spectra sensing accuracy is∼11.5%higher than that of simply extracting resonating modes’wavelength.With the high sensitivity and prediction accuracy,this work opens up a new avenue for integrated intelligent optical sensing.
基金the National Natural Science Foundation of China(Grant Nos.11974058,61307050,and 61701271)the Beijing Nova Program(No.Z201100006820125)+2 种基金Beijing Municipal Science and Technology Commission,in part by the Beijing Natural Science Foundation(No.Z210004)the Shandong Natural Science Foundation(No.ZR2016AM27)the State Key Laboratory of Information Photonics and Optical Communications(No.IPOC2021ZT01),BUPT,China.
文摘Optical microcavities have the ability to confne photons in small mode volumes for long periods of time,greatly enhancing light-matter interactions,and have become one of the research hotspots in international academia.In recent years,sensing applications in complex environments have inspired the development of multimode optical microcavity sensors.These multimode sensors can be used not only for multi-parameter detection but also to improve measurement precision.In this review,we introduce multimode sensing methods based on optical microcavities and present an overview of the multimode single/multi-parameter optical microcavities sensors.Expected further research activities are also put forward.
基金National Natural Science Foundation of China(NSFC)(61501053,61611540346,11474011,11654003,61435001,61471050,61622103)National Key R&D Program of China(2016YFA0301302)+1 种基金Fund of the State Key Laboratory of Information Photonics and Optical Communications(IPOC2017ZT05)Beijing University of Posts and Telecommunications,China
文摘Optical trapping techniques are of great interest since they have the advantage of enabling the direct handling of nanoparticles. Among various optical trapping systems, photonic crystal nanobeam cavities have attracted great attention for integrated on-chip trapping and manipulation. However, optical trapping with high efficiency and low input power is still a big challenge in nanobeam cavities because most of the light energy is confined within the solid dielectric region. To this end, by incorporating a nanoslotted structure into an ultracompact one- dimensional photonic crystal nanobeam cavity structure, we design a promising on-chip device with ultralarge trapping potential depth to enhance the optical trapping characteristic of the cavity. In this work, we first provide a systematic analysis of the optical trapping force for an airborne polystyrene （PS） nanoparticle trapped in a cavity model. Then, to validate the theoretical analysis, the numerical simulation proof is demonstrated in detail by using the three-dimensional finite element method. For trapping a PS nanoparticle of 10 nm radius within the air-slot, a maximum trapping force as high as 8.28 nN/mW and a depth of trapping potential as large as 1.15 × 105 kBTmW-1 are obtained, where kB is the Boltzmann constant and T is the system temperature. We estimate a lateral trapping stiffness of 167.17 pN. nm-1 . mW-1 for a 10 nm radius PS nanoparticle along the cavity x-axis, more than two orders of magnitude higher than previously demonstrated on-chip, near field traps. Moreover, the threshold power for stable trapping as low as 0.087 μW is achieved. In addition, trapping of a single 25 nm radius PS nanoparticle causes a 0.6 nm redshift in peak wavelength. Thus, the proposed cavity device can be used to detect single nanoparticle trapping by monitoring the resonant peak wavelength shift. We believe that the architecture with features of an ultracompact footprint, high integrahility with optical waveguides/cir- cuits, and efficient trapping demonstrated here will provide a promising candidate for developing a lab-on-a-chip device with versatile functionalities.
