In this work,a reflective metasurface connector(RMC)and its application for high-density and wideband spacedivision multiplexing(SDM)are demonstrated.This device features single facet metasurface fabrication over an S...In this work,a reflective metasurface connector(RMC)and its application for high-density and wideband spacedivision multiplexing(SDM)are demonstrated.This device features single facet metasurface fabrication over an SOI platform based on a CMOS compatible process.A minimum fiber-to-fiber insertion loss of 2.9 dB at 1598.24 nm is realized for fan-in-fan-out(FIFO)applications between a single-mode fiber(SMF)array and a multicore fiber(MCF).展开更多
In order to choose the proper radius of oxide aperture for few-mode vertical-cavity surface-emitting lasers （VCSELs）, the influences of oxide aperture size on the multi-transverse-mode behaviors are investigated in ...In order to choose the proper radius of oxide aperture for few-mode vertical-cavity surface-emitting lasers （VCSELs）, the influences of oxide aperture size on the multi-transverse-mode behaviors are investigated in detail. By establishing the effective refractive index model to simulate VCSELs with different radii of oxide apertures, the wavelength and corresponding order of different modes are obtained. VCSELs with three kinds of oxide apertures are manufactured. Then the multi-transverse-mode spectra and near-field are measured. It is found that when the radius is between 1.5 and 4.5μm, few-mode VCSELs can be implemented. The 2.5μm VCSEL manufactured in this paper only emits LP01 mode and LP21 mode. Since the space distance between the two modes is 2μm, it is expected to realize direct-modulation few-mode VCSELs by channel etching or ion implantation between the two modes.展开更多
Space-division multiplexing （SDM） using multi-core fibers （MCFs） and few-mode fibers （FMFs） was proposed as a solution to increase capacity and/or reduce the cost per bit of fiber-optic transmission. Advances in...Space-division multiplexing （SDM） using multi-core fibers （MCFs） and few-mode fibers （FMFs） was proposed as a solution to increase capacity and/or reduce the cost per bit of fiber-optic transmission. Advances in passive and active SDM devices as well as digital signal processing have led to impressive SDM transmission demonstrations in the laboratory. Although the perceived advantages in terms of capacity and cost per bit that SDM offers over parallel SMF bundles are not universally accepted, SDM is beginning to emerge as an indispensable solution in major network segments. The introduction of the spatial degree of freedom allows optical networks to overcome fundamental limitations such as fiber nonlinearity as well practical limitations such as power delivery. We describe these application scenarios that the optical communications industry has already began to explore. From a fundamental science point of view, concepts such as the principal modes, generalized Stokes space, and multi-component solitons discovered in SDM research will likely have a broad impact in other areas of science and engineering.展开更多
High-speed ophthalmic optical coherence tomography(OCT)systems are of interest because they allow rapid,motion-free,and wide-field retinal imaging.Space-division multiplexing optical coherence tomography(SDMOCT)is a h...High-speed ophthalmic optical coherence tomography(OCT)systems are of interest because they allow rapid,motion-free,and wide-field retinal imaging.Space-division multiplexing optical coherence tomography(SDMOCT)is a high-speed imaging technology that takes advantage of the long coherence length of micro electro mechanical vertical cavity surface emitting laser sources to multiplex multiple images along a single imaging depth.We demonstrate wide-field retinal OCT imaging,acquired at an effective A-scan rate of 800,000 A-scans/s with volumetric images covering up to 12.5 mm×7.4 mm on the retina and captured in less than 1 s.A clinical feasibility study was conducted to compare the ophthalmic SDM-OCT with commercial OCT systems,illustrating the high-speed capability of SDM-OCT in a clinical setting.展开更多
Recently, space-division multiplexing （SDM） techniques using multi-core fiber （MCF） and few-mode fiber （FMF） have been introduced into optical fiber communication to increase transmission capacity. Two main type...Recently, space-division multiplexing （SDM） techniques using multi-core fiber （MCF） and few-mode fiber （FMF） have been introduced into optical fiber communication to increase transmission capacity. Two main types of optical fiber amplifiers based on the Erbium- doped fiber （EDF） and the Raman effect have been developed to amplify signals in the MCF and FMF. In this paper, we reviewed the principles and configurations of these amplifiers.展开更多
Advancements in mode-division multiplexing(MDM)techniques,aimed at surpassing the Shannon limit and augmenting transmission capacity,have garnered significant attention in optical fiber communica-tion,propelling the d...Advancements in mode-division multiplexing(MDM)techniques,aimed at surpassing the Shannon limit and augmenting transmission capacity,have garnered significant attention in optical fiber communica-tion,propelling the demand for high-quality multiplexers and demultiplexers.However,the criteria for ideal-mode multiplexers/demultiplexers,such as performance,scalability,compatibility,and ultra-compactness,have only partially been achieved using conventional bulky devices(e.g.,waveguides,grat-ings,and free space optics)—an issue that will substantially restrict the application of MDM techniques.Here,we present a neuro-meta-router(NMR)optimized through deep learning that achieves spatial multi-mode division and supports multi-channel communication,potentially offering scalability,com-patibility,and ultra-compactness.An MDM communication system based on an NMR is theoretically designed and experimentally demonstrated to enable simultaneous and independent multi-dataset transmission,showcasing a capacity of up to 100 gigabits per second(Gbps)and a symbol error rate down to the order of 104,all achieved without any compensation technologies or correlation devices.Our work presents a paradigm that merges metasurfaces,fiber communications,and deep learning,with potential applications in intelligent metasurface-aided optical interconnection,as well as all-optical pat-tern recognition and classification.展开更多
Multiple quantum well(MQW) Ⅲ-nitride diodes that can simultaneously emit and detect light feature an overlapping region between their electroluminescence and responsivity spectra, which allows them to be simultaneous...Multiple quantum well(MQW) Ⅲ-nitride diodes that can simultaneously emit and detect light feature an overlapping region between their electroluminescence and responsivity spectra, which allows them to be simultaneously used as both a transmitter and a receiver in a wireless light communication system. Here, we demonstrate a mobile light communication system using a time-division multiplexing(TDM) scheme to achieve bidirectional data transmission via the same optical channel.Two identical blue MQW diodes are defined by software as a transmitter or a receiver. To address the light alignment issue, an image identification module integrated with a gimbal stabilizer is used to automatically detect the locations of moving targets;thus, underwater audio communication is realized via a mobile blue-light TDM communication mode. This approach not only uses a single link but also integrates mobile nodes in a practical network.展开更多
Dynamically tunable terahertz(THz)beam focusing plays a critical role in emerging applications including reconfigurable imaging,localized spectral analysis,and micro-machining.Conventional methods,however,frequently e...Dynamically tunable terahertz(THz)beam focusing plays a critical role in emerging applications including reconfigurable imaging,localized spectral analysis,and micro-machining.Conventional methods,however,frequently employ complex wavefront modulators and external control algorithms,resulting in increased system footprint and limited tuning efficiency.In this work,we present an all-silicon mechanically rotatable cascaded metasurface capable of dynamic THz beam focusing.By independently adjusting the relative rotation angles between the two metasurface layers,real-time repositioning of the focal spot is achieved for orthogonal circular polarization channels.The proposed design facilitates polarization-division multiplexing without requiring external algorithms or active materials while preserving high focusing efficiency and beam quality across a predefined focal plane.Numerical simulations reveal a quasi-linear shift of the focal position with the rotation angle,with stable focusing efficiency and full-width at half-maximum observed in both polarization channels.This strategy offers an efficient and reliable approach to dynamic wavefront control for compact,reconfigurable THz imaging,sensing,and communication systems.展开更多
The exponential growth in data traffic has driven significant research into maximizing the capacity of free-space optical(FSO)communication systems.Orbital angular momentum(OAM)multiplexing offers a promising approach...The exponential growth in data traffic has driven significant research into maximizing the capacity of free-space optical(FSO)communication systems.Orbital angular momentum(OAM)multiplexing offers a promising approach by using spatially structured beams with helical wavefronts to achieve higher data transmission rates.However,conventional electronic convolutional-neural-network-based OAM demultiplexing schemes exhibit substantial computational and energy efficiency limitations.展开更多
The implementation of multiple pathogen testing is essential for a rapid response to future outbreaks and for reducing disease transmission.This study introduces a 96-channel microfluidic chip,fabricated through a mol...The implementation of multiple pathogen testing is essential for a rapid response to future outbreaks and for reducing disease transmission.This study introduces a 96-channel microfluidic chip,fabricated through a molding process,which enables the batch detection of pathogens.It explores the rapid lysis and elution processes of pathogens within the microfluidic chips to ensure that nucleic acid extraction,elution,and amplification are completed entirely within the chip.This chip can extract nucleic acids from samples in just 10 min,achieving an extraction efficiency comparable to that of traditional in-tube methods.An oil phase is pre-loaded into the chip to effectively prevent aerosol contamination.This approach allows for the simultaneous detection of 21 common respiratory pathogens,with a detection limit of 10 copies per reaction.Furthermore,applications involving clinical samples demonstrate significant practicality.Compared to many traditional in-tube pathogen detection methods and molecular biology technologies that utilize microfluidic chips,this detection chip not only enables simultaneous detection of multiple pathogens but also demonstrates high sensitivity.展开更多
Rice, a global staple food, is critical for food security. The cultivated Oryza sativa, domesticated from wild O. rufipogon, derives~80%of its 993 identified domestication-related genes from O. rufipogon and 20%from S...Rice, a global staple food, is critical for food security. The cultivated Oryza sativa, domesticated from wild O. rufipogon, derives~80%of its 993 identified domestication-related genes from O. rufipogon and 20%from South/Southeast Asian wild O. nivara(Jing et al., 2023). Genes like An-1, BH4, PROG1,SH4, Rc, Rd, and GS3—which regulate awn length, hull color,til er angle, seed shattering, pericarp color, seed length, and thousand-grain weight, respectively—were selected against during domestication to form modern O. sativa(Yu et al., 2021).However, domestication and yield-focused breeding eliminated wild rice's valuable genes(e.g., for disease resistance, stress tolerance, nutrition), narrowing genetic diversity and impeding efforts to meet growing societal demands.展开更多
Herein,an attention-grabbing and up-to-date review related to major multiplexing techniques is presented which in-cludes wavelength division multiplexing(WDM),polarization division multiplexing(PDM),space division mul...Herein,an attention-grabbing and up-to-date review related to major multiplexing techniques is presented which in-cludes wavelength division multiplexing(WDM),polarization division multiplexing(PDM),space division multiplexing(SDM),mode division multiplexing(MDM)and orbital angular momentum multiplexing(OAMM).Multiplexing is a mech-anism by which multiple signals are combined into a shared channel used to showcase the maximum capacity of the op-tical links.However,it is critical to develop hybrid multiplexing methods to allow enhanced channel numbers.In this re-view,we have also included hybrid multiplexing techniques such as WDM-PDM,WDM-MDM and PDM-MDM.It is prob-able to attain N×M channels by utilizing N wavelengths and M guided-modes by simply utilizing hybrid WDM-MDM(de)multiplexers.To the best of our knowledge,this review paper is one of its kind which has highlighted the most prom-inent and recent signs of progress in multiplexing techniques in one place.展开更多
Orbital angular momentum(OAM),described by an azimuthal phase term expej lθT,has unbound orthogonal states with different topological charges l.Therefore,with the explosive growth of global communication capacity,esp...Orbital angular momentum(OAM),described by an azimuthal phase term expej lθT,has unbound orthogonal states with different topological charges l.Therefore,with the explosive growth of global communication capacity,especially for short-distance optical interconnects,light-carrying OAM has proved its great potential to improve transmission capacity and spectral efficiency in the space-division multiplexing system due to its orthogonality,security,and compatibility with other techniques.Meanwhile,100-m freespace optical interconnects become an alternative solution for the“last mile”problem and provide interbuilding communication.We experimentally demonstrate a 260-m secure optical interconnect using OAM multiplexing and 16-ary quadrature amplitude modulation(16-QAM)signals.We study the beam wandering,power fluctuation,channel cross talk,bit-error-rate performance,and link security.Additionally,we also investigate the link performance for 1-to-9 multicasting at the range of 260 m.Considering that the power distribution may be affected by atmospheric turbulence,we introduce an offline feedback process to make it flexibly controllable.展开更多
The interleaving/multiplexing technique was used to realize a 200?MHz real time data acquisition system. Two 100?MHz ADC modules worked parallelly and every ADC plays out data in ping pang fashion. The design improv...The interleaving/multiplexing technique was used to realize a 200?MHz real time data acquisition system. Two 100?MHz ADC modules worked parallelly and every ADC plays out data in ping pang fashion. The design improved the system conversion rata to 200?MHz and reduced the speed of data transporting and storing to 50?MHz. The high speed HDPLD and ECL logic parts were used to control system timing and the memory address. The multi layer print board and the shield were used to decrease interference produced by the high speed circuit. The system timing was designed carefully. The interleaving/multiplexing technique could improve the system conversion rata greatly while reducing the speed of external digital interfaces greatly. The design resolved the difficulties in high speed system effectively. The experiment proved the data acquisition system is stable and accurate.展开更多
Flat optical elements have attracted enormous attentions and act as promising candidates for the next generation of optical components.As one of the most outstanding representatives,liquid crystal(LC)has been widely a...Flat optical elements have attracted enormous attentions and act as promising candidates for the next generation of optical components.As one of the most outstanding representatives,liquid crystal(LC)has been widely applied in flat panel display industries and inspires the wavefront modulation with the development of LC alignment techniques.However,most LC elements perform only one type of optical manipulation and are difficult to realize the multifunctionality and light integration.Here,flat multifunctional liquid crystal elements(FMLCEs),merely composed of anisotropic LC molecules with space-variant orientations,are presented for multichannel information manipulation by means of polarization,space and wavelength multiplexing.Specifically,benefiting from the unique light response with the change of the incident polarization,observation plane,and working wavelength,a series of FMLCEs are demonstrated to achieve distinct near-and far-field display functions.The proposed strategy takes full advantage of basic optical parameters as the decrypted keys to improve the information capacity and security,and we expect it to find potential applications in information encryption,optical anti-counterfeiting,virtual/augmented reality,etc.展开更多
The multiplexing ability of a novel multiplexing fiber Bragg grating(FBG)method based on Optical Time Domain Reflecto meter(OTDR)and Time Division Multiplexing TDM technologies has been theoretically analyzed and stud...The multiplexing ability of a novel multiplexing fiber Bragg grating(FBG)method based on Optical Time Domain Reflecto meter(OTDR)and Time Division Multiplexing TDM technologies has been theoretically analyzed and studied.This method permits the interrogation of hundreds of identical FBGs with low reflectivity in a single fiber,making the FBG sensors more applicable in the aerospace health monitoring engineering.The analysis shows that the multiplexing ability can be greatly improved if the FBG reflectivity is sufficiently low.And hence,an inexpensive large-scale distributed sensing system based on this method can be realized,When evaluating the multiplexing ability of this system,we propose for the first time that the interference effect of multi-reflections among FBGs should be taken into consideration.展开更多
Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface ho...Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface holography can only realize static manipulation.In this study,we propose and demonstrate a multiplexing metasurface technique combined with multiwavelength code-division multiplexing(CDM)to realize dynamic manipulation.Multicolor code references are utilized to record information within a single metasurface and increase the information capacity and security for anticracks.A total of 48 monochrome images consisting of pure color characters and multilevel color video frames were reconstructed in dual polarization channels of the birefringent metasurface to exhibit high information density,and a video was displayed via sequential illumination of the corresponding code patterns to verify the ability of dynamic manipulation.Our approach demonstrates significant application potential in optical data storage,optical encryption,multiwavelengthversatile diffractive optical elements,and stimulated emission depletion microscopy.展开更多
As a promising counterpart of two-dimensional metamaterials,metasurfaces enable to arbitrarily control the wavefront of light at subwavelength scale and hold promise for planar holography and applicable multiplexing d...As a promising counterpart of two-dimensional metamaterials,metasurfaces enable to arbitrarily control the wavefront of light at subwavelength scale and hold promise for planar holography and applicable multiplexing devices.Nevertheless,the degrees of freedom(DoF)to orthogonally multiplex data have been almost exhausted.Compared with state-of-theart methods that extensively employ the orthogonal basis such as wavelength,polarization or orbital angular momentum,we propose an unprecedented method of peristrophic multiplexing by combining the spatial frequency orthogonality with the subwavelength detour phase principle.The orthogonal relationship between the spatial frequency of incident light and the locally shifted building blocks of metasurfaces can be regarded as an additional DoF.We experimentally demonstrate the viability of the multiplexed holograms.Moreover,this newly-explored orthogonality is compatible with conventional DoFs.Our findings will contribute to the development of multiplexing metasurfaces and provide a novel solution to nanophotonics,such as large-capacity chip-scale devices and highly integrated communication.展开更多
In this paper, the bit synchronization algorithms in GNSS receiver are introduced, including the traditional histogram method, K-P algorithm and Viterbi algorithm. The FPGA implementation is also included. A novel tim...In this paper, the bit synchronization algorithms in GNSS receiver are introduced, including the traditional histogram method, K-P algorithm and Viterbi algorithm. The FPGA implementation is also included. A novel time division multiplexing technology （TDM） based on multi-channel shared synchronizer is proposed in this paper to solve the constrained hardware resource problem of multi-system satellite navigation receiver. Through the using of control state machine and data register structure, we realize the multiplexing of bit synchronizer of navigation receiver, which saves the hardware resource. After the experiment, it can be verified that the receiver based on the bit synchronization and multiplexing technology can correctly restore the navigation information.展开更多
Polarization-division multiplexing(PDM)with modulation in the nonlinear frequency domain consisting of the discrete and/or continuous spectrum has been recently regarded as a useful method to be utilized in optical fi...Polarization-division multiplexing(PDM)with modulation in the nonlinear frequency domain consisting of the discrete and/or continuous spectrum has been recently regarded as a useful method to be utilized in optical fiber communication system.It can compensate the optical fiber nonlinearity based on the nonlinear Fourier transform(NFT).In this paper,we combine PDM with the method of nonlinear frequency division multiplexing(NFDM)and demonstrate the achievable transmission rate by increasing the number of multiplexing nonlinear channels.For the selected subcarriers(i.e.32,64,and 128),the transmission rates are 64 Gbit/s,76.8 Gbit/s,and 109.7 Gbit/s respectively by applying 64-quadrature amplitude modulation(64-QAM)on the nonlinear continuous spectrum.For the transmission distance shorter than 1200 km,the transmission rate of 128-NFDM PDM system can even reach up to 153.6 Gbit/s.展开更多
基金National Key Research and Development Program of China(2023YFB2905502)Explorers Program of Shanghai(Basic Research Funding)(24TS1401000)。
文摘In this work,a reflective metasurface connector(RMC)and its application for high-density and wideband spacedivision multiplexing(SDM)are demonstrated.This device features single facet metasurface fabrication over an SOI platform based on a CMOS compatible process.A minimum fiber-to-fiber insertion loss of 2.9 dB at 1598.24 nm is realized for fan-in-fan-out(FIFO)applications between a single-mode fiber(SMF)array and a multicore fiber(MCF).
基金supported by the National Basic Research Program of China(No.2014CB3400102)the National Natural Science Foundation of China(No.61335004)+1 种基金the National High Technology Research and Development Program of China(No.2015AA017101)the National Key Technologies R&D Program of China(No.2016YFB0400603)
文摘In order to choose the proper radius of oxide aperture for few-mode vertical-cavity surface-emitting lasers （VCSELs）, the influences of oxide aperture size on the multi-transverse-mode behaviors are investigated in detail. By establishing the effective refractive index model to simulate VCSELs with different radii of oxide apertures, the wavelength and corresponding order of different modes are obtained. VCSELs with three kinds of oxide apertures are manufactured. Then the multi-transverse-mode spectra and near-field are measured. It is found that when the radius is between 1.5 and 4.5μm, few-mode VCSELs can be implemented. The 2.5μm VCSEL manufactured in this paper only emits LP01 mode and LP21 mode. Since the space distance between the two modes is 2μm, it is expected to realize direct-modulation few-mode VCSELs by channel etching or ion implantation between the two modes.
基金This work has been supported in part by the National Basic Research Program of China （973） （No. 2014CB340104/1）, the National Natural Science Foundation of China （NSFC） （Grant Nos. 61377076, 61307085 and 61431009）.
文摘Space-division multiplexing （SDM） using multi-core fibers （MCFs） and few-mode fibers （FMFs） was proposed as a solution to increase capacity and/or reduce the cost per bit of fiber-optic transmission. Advances in passive and active SDM devices as well as digital signal processing have led to impressive SDM transmission demonstrations in the laboratory. Although the perceived advantages in terms of capacity and cost per bit that SDM offers over parallel SMF bundles are not universally accepted, SDM is beginning to emerge as an indispensable solution in major network segments. The introduction of the spatial degree of freedom allows optical networks to overcome fundamental limitations such as fiber nonlinearity as well practical limitations such as power delivery. We describe these application scenarios that the optical communications industry has already began to explore. From a fundamental science point of view, concepts such as the principal modes, generalized Stokes space, and multi-component solitons discovered in SDM research will likely have a broad impact in other areas of science and engineering.
基金National Science Foundation(DBI-1455613,IIP-1623823,IIP-1640707)National Institutes of Health(R01-EB025209)。
文摘High-speed ophthalmic optical coherence tomography(OCT)systems are of interest because they allow rapid,motion-free,and wide-field retinal imaging.Space-division multiplexing optical coherence tomography(SDMOCT)is a high-speed imaging technology that takes advantage of the long coherence length of micro electro mechanical vertical cavity surface emitting laser sources to multiplex multiple images along a single imaging depth.We demonstrate wide-field retinal OCT imaging,acquired at an effective A-scan rate of 800,000 A-scans/s with volumetric images covering up to 12.5 mm×7.4 mm on the retina and captured in less than 1 s.A clinical feasibility study was conducted to compare the ophthalmic SDM-OCT with commercial OCT systems,illustrating the high-speed capability of SDM-OCT in a clinical setting.
文摘Recently, space-division multiplexing （SDM） techniques using multi-core fiber （MCF） and few-mode fiber （FMF） have been introduced into optical fiber communication to increase transmission capacity. Two main types of optical fiber amplifiers based on the Erbium- doped fiber （EDF） and the Raman effect have been developed to amplify signals in the MCF and FMF. In this paper, we reviewed the principles and configurations of these amplifiers.
基金supported by the National Key Research and Development Program of China(2023YFB2804704)the National Natural Science Foundation of China(12174292,12374278,and 62105250).
文摘Advancements in mode-division multiplexing(MDM)techniques,aimed at surpassing the Shannon limit and augmenting transmission capacity,have garnered significant attention in optical fiber communica-tion,propelling the demand for high-quality multiplexers and demultiplexers.However,the criteria for ideal-mode multiplexers/demultiplexers,such as performance,scalability,compatibility,and ultra-compactness,have only partially been achieved using conventional bulky devices(e.g.,waveguides,grat-ings,and free space optics)—an issue that will substantially restrict the application of MDM techniques.Here,we present a neuro-meta-router(NMR)optimized through deep learning that achieves spatial multi-mode division and supports multi-channel communication,potentially offering scalability,com-patibility,and ultra-compactness.An MDM communication system based on an NMR is theoretically designed and experimentally demonstrated to enable simultaneous and independent multi-dataset transmission,showcasing a capacity of up to 100 gigabits per second(Gbps)and a symbol error rate down to the order of 104,all achieved without any compensation technologies or correlation devices.Our work presents a paradigm that merges metasurfaces,fiber communications,and deep learning,with potential applications in intelligent metasurface-aided optical interconnection,as well as all-optical pat-tern recognition and classification.
基金jointly supported by the National Natural Science Foundation of China (U21A20495)Natural Science Foundation of Jiangsu Province (BG2024023)+1 种基金National Key Research and Development Program of China (2022YFE0112000)111 Project (D17018)。
文摘Multiple quantum well(MQW) Ⅲ-nitride diodes that can simultaneously emit and detect light feature an overlapping region between their electroluminescence and responsivity spectra, which allows them to be simultaneously used as both a transmitter and a receiver in a wireless light communication system. Here, we demonstrate a mobile light communication system using a time-division multiplexing(TDM) scheme to achieve bidirectional data transmission via the same optical channel.Two identical blue MQW diodes are defined by software as a transmitter or a receiver. To address the light alignment issue, an image identification module integrated with a gimbal stabilizer is used to automatically detect the locations of moving targets;thus, underwater audio communication is realized via a mobile blue-light TDM communication mode. This approach not only uses a single link but also integrates mobile nodes in a practical network.
基金supported by the National Natural Science Foundation of China(Grants U22A2008,12404484,12464016,and 62405219)the Double First Class Joint Special Key Project of Yunnan Science and Technology Department and Yunnan University(Grant 202401BF070001-012)Sichuan Provincial Science and Technology Support Program(Grant 25QNJJ2419).
文摘Dynamically tunable terahertz(THz)beam focusing plays a critical role in emerging applications including reconfigurable imaging,localized spectral analysis,and micro-machining.Conventional methods,however,frequently employ complex wavefront modulators and external control algorithms,resulting in increased system footprint and limited tuning efficiency.In this work,we present an all-silicon mechanically rotatable cascaded metasurface capable of dynamic THz beam focusing.By independently adjusting the relative rotation angles between the two metasurface layers,real-time repositioning of the focal spot is achieved for orthogonal circular polarization channels.The proposed design facilitates polarization-division multiplexing without requiring external algorithms or active materials while preserving high focusing efficiency and beam quality across a predefined focal plane.Numerical simulations reveal a quasi-linear shift of the focal position with the rotation angle,with stable focusing efficiency and full-width at half-maximum observed in both polarization channels.This strategy offers an efficient and reliable approach to dynamic wavefront control for compact,reconfigurable THz imaging,sensing,and communication systems.
文摘The exponential growth in data traffic has driven significant research into maximizing the capacity of free-space optical(FSO)communication systems.Orbital angular momentum(OAM)multiplexing offers a promising approach by using spatially structured beams with helical wavefronts to achieve higher data transmission rates.However,conventional electronic convolutional-neural-network-based OAM demultiplexing schemes exhibit substantial computational and energy efficiency limitations.
基金supported by grants from the National Key Research and Development Program of China(Nos.2023YFA0915200,2023YFA0915204)the Equipment Research and Development Projects of the Chinese Academy of Sciences(No.PTYQ2024YZ0010)+3 种基金the Science and Technology Commission of Shanghai Municipality Project(No.XTCX-KJ-2024-038)the Natural Science Foundation of Hebei Province of China(No.H2024206249)the Postdoctoral Fellowship Program of CPSF(No.GZC20232838)Science and Technology Commission of Shanghai Municipality(No.22S31901700).
文摘The implementation of multiple pathogen testing is essential for a rapid response to future outbreaks and for reducing disease transmission.This study introduces a 96-channel microfluidic chip,fabricated through a molding process,which enables the batch detection of pathogens.It explores the rapid lysis and elution processes of pathogens within the microfluidic chips to ensure that nucleic acid extraction,elution,and amplification are completed entirely within the chip.This chip can extract nucleic acids from samples in just 10 min,achieving an extraction efficiency comparable to that of traditional in-tube methods.An oil phase is pre-loaded into the chip to effectively prevent aerosol contamination.This approach allows for the simultaneous detection of 21 common respiratory pathogens,with a detection limit of 10 copies per reaction.Furthermore,applications involving clinical samples demonstrate significant practicality.Compared to many traditional in-tube pathogen detection methods and molecular biology technologies that utilize microfluidic chips,this detection chip not only enables simultaneous detection of multiple pathogens but also demonstrates high sensitivity.
基金supported by the Biological BreedingMajor Projects(2023ZD04076)the National Natural Science Foundation of China(32300312)+2 种基金the Innovation Program of Chinses Academy of Agricultural Sciences(CAAS-CSIAF-202303)the Guangdong Basic and Applied Basic Research Foundation(2020B1515120086)the KeyArea Research and Development Program of Guangdong Province(2021B0707010006)。
文摘Rice, a global staple food, is critical for food security. The cultivated Oryza sativa, domesticated from wild O. rufipogon, derives~80%of its 993 identified domestication-related genes from O. rufipogon and 20%from South/Southeast Asian wild O. nivara(Jing et al., 2023). Genes like An-1, BH4, PROG1,SH4, Rc, Rd, and GS3—which regulate awn length, hull color,til er angle, seed shattering, pericarp color, seed length, and thousand-grain weight, respectively—were selected against during domestication to form modern O. sativa(Yu et al., 2021).However, domestication and yield-focused breeding eliminated wild rice's valuable genes(e.g., for disease resistance, stress tolerance, nutrition), narrowing genetic diversity and impeding efforts to meet growing societal demands.
基金financially supported by the Russian Foundation for Basic Research(grant No.18-29-20045)for WDM,MDM and hybrid WDM-MDM,WDM-PDM sectionsthe Russian Science Foundation(grant No.21-79-20075)for PDM,OAMM and hybrid PDM-MDM sectionsthe Ministry of Science and Higher Education of the Russian Federation under the FSRC"Crystallography and Photonics"of the Russian Academy of Sciences(the state task No.007-GZ/Ch3363/26)for comparative analysis.
文摘Herein,an attention-grabbing and up-to-date review related to major multiplexing techniques is presented which in-cludes wavelength division multiplexing(WDM),polarization division multiplexing(PDM),space division multiplexing(SDM),mode division multiplexing(MDM)and orbital angular momentum multiplexing(OAMM).Multiplexing is a mech-anism by which multiple signals are combined into a shared channel used to showcase the maximum capacity of the op-tical links.However,it is critical to develop hybrid multiplexing methods to allow enhanced channel numbers.In this re-view,we have also included hybrid multiplexing techniques such as WDM-PDM,WDM-MDM and PDM-MDM.It is prob-able to attain N×M channels by utilizing N wavelengths and M guided-modes by simply utilizing hybrid WDM-MDM(de)multiplexers.To the best of our knowledge,this review paper is one of its kind which has highlighted the most prom-inent and recent signs of progress in multiplexing techniques in one place.
基金supported by the National Natural Science Foundation of China (Grant Nos.62125503,62261160388,and 62101198)the Natural Science Foundation of Hubei Province of China (Grant Nos.2021CFB011 and 2023AFA028)+2 种基金the Key R&D Program of Hubei Province of China (Grant Nos.2020BAB001 and 2021BAA024)Shenzhen Science and Technology Program (Grant No.JCYJ20200109114018750)the Innovation Project of Optics Valley Laboratory (Grant Nos.OVL2021BG004 and OVL2023ZD004).
文摘Orbital angular momentum(OAM),described by an azimuthal phase term expej lθT,has unbound orthogonal states with different topological charges l.Therefore,with the explosive growth of global communication capacity,especially for short-distance optical interconnects,light-carrying OAM has proved its great potential to improve transmission capacity and spectral efficiency in the space-division multiplexing system due to its orthogonality,security,and compatibility with other techniques.Meanwhile,100-m freespace optical interconnects become an alternative solution for the“last mile”problem and provide interbuilding communication.We experimentally demonstrate a 260-m secure optical interconnect using OAM multiplexing and 16-ary quadrature amplitude modulation(16-QAM)signals.We study the beam wandering,power fluctuation,channel cross talk,bit-error-rate performance,and link security.Additionally,we also investigate the link performance for 1-to-9 multicasting at the range of 260 m.Considering that the power distribution may be affected by atmospheric turbulence,we introduce an offline feedback process to make it flexibly controllable.
文摘The interleaving/multiplexing technique was used to realize a 200?MHz real time data acquisition system. Two 100?MHz ADC modules worked parallelly and every ADC plays out data in ping pang fashion. The design improved the system conversion rata to 200?MHz and reduced the speed of data transporting and storing to 50?MHz. The high speed HDPLD and ECL logic parts were used to control system timing and the memory address. The multi layer print board and the shield were used to decrease interference produced by the high speed circuit. The system timing was designed carefully. The interleaving/multiplexing technique could improve the system conversion rata greatly while reducing the speed of external digital interfaces greatly. The design resolved the difficulties in high speed system effectively. The experiment proved the data acquisition system is stable and accurate.
基金the supports from the National Natural Science Foundation of China (61905073, 61835004, 62134001, 61905031, 62105263, 62275077)Fundamental Research Fund for the Central Universities (531118010189, 310202011qd002)+1 种基金the support from Xi’an Science and Technology Association Youth Talent Support Project (095920211306)the Postdoctoral Innovation Talent Support Program of China (BX20220388)
文摘Flat optical elements have attracted enormous attentions and act as promising candidates for the next generation of optical components.As one of the most outstanding representatives,liquid crystal(LC)has been widely applied in flat panel display industries and inspires the wavefront modulation with the development of LC alignment techniques.However,most LC elements perform only one type of optical manipulation and are difficult to realize the multifunctionality and light integration.Here,flat multifunctional liquid crystal elements(FMLCEs),merely composed of anisotropic LC molecules with space-variant orientations,are presented for multichannel information manipulation by means of polarization,space and wavelength multiplexing.Specifically,benefiting from the unique light response with the change of the incident polarization,observation plane,and working wavelength,a series of FMLCEs are demonstrated to achieve distinct near-and far-field display functions.The proposed strategy takes full advantage of basic optical parameters as the decrypted keys to improve the information capacity and security,and we expect it to find potential applications in information encryption,optical anti-counterfeiting,virtual/augmented reality,etc.
基金Foundation item:National Natural Science Foundation of China(10376001)
文摘The multiplexing ability of a novel multiplexing fiber Bragg grating(FBG)method based on Optical Time Domain Reflecto meter(OTDR)and Time Division Multiplexing TDM technologies has been theoretically analyzed and studied.This method permits the interrogation of hundreds of identical FBGs with low reflectivity in a single fiber,making the FBG sensors more applicable in the aerospace health monitoring engineering.The analysis shows that the multiplexing ability can be greatly improved if the FBG reflectivity is sufficiently low.And hence,an inexpensive large-scale distributed sensing system based on this method can be realized,When evaluating the multiplexing ability of this system,we propose for the first time that the interference effect of multi-reflections among FBGs should be taken into consideration.
基金the National Key R&D Program of China(2021YFA1401200)Beijing Outstanding Young Scientist Program(BJJWZYJH01201910007022)+2 种基金National Natural Science Foundation of China(No.U21A20140,No.92050117)Beijing Municipal Science&Technology Commission,Administrative Commission of Zhongguancun Science Park(No.Z211100004821009)X.Li acknowledges the support from Beijing Institute of Technology Research Fund Program for Young Scholars(XSQD-201904005).
文摘Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface holography can only realize static manipulation.In this study,we propose and demonstrate a multiplexing metasurface technique combined with multiwavelength code-division multiplexing(CDM)to realize dynamic manipulation.Multicolor code references are utilized to record information within a single metasurface and increase the information capacity and security for anticracks.A total of 48 monochrome images consisting of pure color characters and multilevel color video frames were reconstructed in dual polarization channels of the birefringent metasurface to exhibit high information density,and a video was displayed via sequential illumination of the corresponding code patterns to verify the ability of dynamic manipulation.Our approach demonstrates significant application potential in optical data storage,optical encryption,multiwavelengthversatile diffractive optical elements,and stimulated emission depletion microscopy.
基金supported by the Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)No.HRTP202231partially supported by the Agency for Science,Technology,and Research(A*STAR)under AME IRG Grant Nos.A20E5c0095,and CDF Grant No.C210112044。
文摘As a promising counterpart of two-dimensional metamaterials,metasurfaces enable to arbitrarily control the wavefront of light at subwavelength scale and hold promise for planar holography and applicable multiplexing devices.Nevertheless,the degrees of freedom(DoF)to orthogonally multiplex data have been almost exhausted.Compared with state-of-theart methods that extensively employ the orthogonal basis such as wavelength,polarization or orbital angular momentum,we propose an unprecedented method of peristrophic multiplexing by combining the spatial frequency orthogonality with the subwavelength detour phase principle.The orthogonal relationship between the spatial frequency of incident light and the locally shifted building blocks of metasurfaces can be regarded as an additional DoF.We experimentally demonstrate the viability of the multiplexed holograms.Moreover,this newly-explored orthogonality is compatible with conventional DoFs.Our findings will contribute to the development of multiplexing metasurfaces and provide a novel solution to nanophotonics,such as large-capacity chip-scale devices and highly integrated communication.
基金the National Natural Science Foundation of China under Grant，the China Postdoctoral Science Foundation under Grant No.2013M530526，the Fundamental Research Funds for the Central Universities under Grant No.FRF-TP-14-046A2
文摘In this paper, the bit synchronization algorithms in GNSS receiver are introduced, including the traditional histogram method, K-P algorithm and Viterbi algorithm. The FPGA implementation is also included. A novel time division multiplexing technology （TDM） based on multi-channel shared synchronizer is proposed in this paper to solve the constrained hardware resource problem of multi-system satellite navigation receiver. Through the using of control state machine and data register structure, we realize the multiplexing of bit synchronizer of navigation receiver, which saves the hardware resource. After the experiment, it can be verified that the receiver based on the bit synchronization and multiplexing technology can correctly restore the navigation information.
文摘Polarization-division multiplexing(PDM)with modulation in the nonlinear frequency domain consisting of the discrete and/or continuous spectrum has been recently regarded as a useful method to be utilized in optical fiber communication system.It can compensate the optical fiber nonlinearity based on the nonlinear Fourier transform(NFT).In this paper,we combine PDM with the method of nonlinear frequency division multiplexing(NFDM)and demonstrate the achievable transmission rate by increasing the number of multiplexing nonlinear channels.For the selected subcarriers(i.e.32,64,and 128),the transmission rates are 64 Gbit/s,76.8 Gbit/s,and 109.7 Gbit/s respectively by applying 64-quadrature amplitude modulation(64-QAM)on the nonlinear continuous spectrum.For the transmission distance shorter than 1200 km,the transmission rate of 128-NFDM PDM system can even reach up to 153.6 Gbit/s.
