Dissipative Kerr solitons in optical microcavities enable various stable states involving multi-soliton and perfect soliton crystal(PSC),leading to widespread applications.However,the triggering condition and switchin...Dissipative Kerr solitons in optical microcavities enable various stable states involving multi-soliton and perfect soliton crystal(PSC),leading to widespread applications.However,the triggering condition and switching dynamics of the PSC and multi-soliton states(MSs)remain unexplored,which makes it challenging to selectively trigger the PSC/MS state for distinct area.Here,we theoretically and experimentally investigate the realization and switching of multi-/single-soliton and PSC states by engineering the periodic intracavity potential field constructed by control laser in a high-Q microrod cavity.We show that,by varying the parameters of the control laser,the PSC and multi-/single-soliton states can be selectively excited,and the soliton dynamics depends on the chaotic regime.We establish a fundamental link between the PSC switching behavior with the transient chaotic regime.Using such relation,we also demonstrate the switching and dynamical phenomena involving the conversion between PSC and MS,and soliton crystal melting and recrystallization.Our work provides additional routes for manipulation of soliton temporal and spectral profiles in optical microcavity systems and enables soliton generation on demand with desired states inside a single device.展开更多
Optical control of magnons in two-dimensional(2D)materials promises new functionalities for spintronics and magnonics in atomically thin devices.Here,we report control of magnon dynamics,using laser polarization,in a ...Optical control of magnons in two-dimensional(2D)materials promises new functionalities for spintronics and magnonics in atomically thin devices.Here,we report control of magnon dynamics,using laser polarization,in a ferromagnetic van der Waals(vdW)material,Fe3.6Co1.4GeTe2.The magnon amplitude,frequency,and lifetime are controlled and monitored by time-resolved pump-probe spectroscopy.We show substantial(over 25%)and continuous modulation of magnon dynamics as a function of incident laser polarization.Our results suggest that the modification of the effective demagnetization field and magnetic anisotropy by the pump laser pulses with different polarizations is due to anisotropic optical absorption.This implies that pump laser pulses modify the local spin environment,which enables the launch of magnons with tunable dynamics.Our first-principles calculations confirm the anisotropic optical absorption of different crystal orientations.Our findings suggest a new route for the development of opto-spintronic or opto-magnonic devices.展开更多
Optical control of exotic properties in strongly correlated electron materials is very attractive owing to their potential applications in optical and electronic devices.Herein,we demonstrate a vertical heterojunction...Optical control of exotic properties in strongly correlated electron materials is very attractive owing to their potential applications in optical and electronic devices.Herein,we demonstrate a vertical heterojunction made of a correlated electron oxide thin film VO_(2) and a conductive 0.05 wt% Nb-doped TiO_(2) single crystal,whose metal-insulator transition(MIT)across the nanoscale heterointerface can be efficiently modulated by visible light irradiation.The magnitude of the MIT decreases from ~350 in the dark state to ~7 in the illuminated state,obeying a power law with respect to the light power density.The junction resistance is switched in a reversible and synchronous manner by turning light on and off.The optical tunability of it is also exponentially proportional to the light power density,and a 320-fold on/off ratio is achieved with an irradiance of 65.6 mW cm^(-2) below the MIT temperature.While the VO_(2) thin film is metallic above the MIT temperature,the optical tunability is remarkably weakened,with a one-fold change remaining under light illumination.These results are co-attributed to a net reduction(~15 meV)in the apparent barrier height and the photocarrier-injection-induced metallization of the VO_(2) heterointerface through a photovoltaic effect,which is induced by deep defect level transition upon the visible light irradiance at low temperature.Additionally,the optical tunability is minimal,resulting from the quite weak modulation of the already metallic band structure in the Schottky-type junction above the MIT temperature.This work enables a remotely optical scheme to manipulate the MIT,implying potential uncooled photodetection and photoswitch applications.展开更多
Genetic encoding of photocaged noncanonical amino acids provides a powerful tool to study protein functions through optical control but is not yet available for acidic amino acids.Herein,we report the first site-speci...Genetic encoding of photocaged noncanonical amino acids provides a powerful tool to study protein functions through optical control but is not yet available for acidic amino acids.Herein,we report the first site-specific genetic encoding of a photocaged glutamate,4-methoxy-7-nitroindolinyl caged glutamate(MNI-Glu),into recombinant proteins via an expanded genetic code through evolved EcLeuRS/tRNA pair.Using two enzymes as examples,we demonstrate that substituting the conserved-active-site glutamate of a secreted alkaline phosphatase and a protease HRV3C to MNI-Glu allows photoregulatory control of their enzymatic activities.Our approach is an important addition to the photocaged noncanonical amino-acid toolbox and provides a general method to photocontrol protein activity based on caging a critical glutamate.展开更多
The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features ...The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features such as rapid provisioning,automated protection and restoration(P&R),efficient resource allocation,and support for different quality of service(QoS) requirements.In this paper,we propose a novel stateful PCE-cloud(SPC)based architecture of GMPLS optical networks for cloud services.The cloud computing technologies(e.g.virtualization and parallel computing) are applied to the construction of SPC for improving the reliability and maximizing resource utilization.The functions of SPC and GMPLS based control plane are expanded according to the features of cloud services for different QoS requirements.The architecture and detailed description of the components of SPC are provided.Different potential cooperation relationships between public stateful PCE cloud(PSPC) and region stateful PCE cloud(RSPC) are investigated.Moreover,we present the policy-enabled and constraint-based routing scheme base on the cooperation of PSPC and RSPC.Simulation results for verifying the performance of routing and control plane reliability are analyzed.展开更多
We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorpt...We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorption and dispersion of the probe field can be dramatically influenced by the relative phase between applied fields and intensity of the Gaussian laser beams.Transient and steady-state behaviors of the probe field absorption and dispersion are discussed to estimate the required switching time.The estimated range is between 5-8 ps for subluminal to superluminal light propagation.展开更多
A technique capable of focusing and bending electromagnetic (EM) waves through plasmonic gratings with equally spaced alternately tapered slits has been introduced. Phase resonances are observed in the optical respo...A technique capable of focusing and bending electromagnetic (EM) waves through plasmonic gratings with equally spaced alternately tapered slits has been introduced. Phase resonances are observed in the optical response of transmission gratings, and the EM wave passes through the tuning slits in the form of surface plasmon polaritons (SPPs) and obtains the required phase retardation to focus at the focal plane. The bending effect is achieved by constructing an asymmetric phase front which results from the tapered slits and gradient refractive index (GRIN) distribution of the dielectric material. Rigorous electromagnetic analysis by using the two-dimensional (2D) finite difference time domain (FDTD) method is employed to verify our proposed designs. When the EM waves are incident at an angle on the optical axis, the beam splitting effect can also be achieved. These index-modulated slits are demonstrated to have unique advantages in beam manipulation compared with the width-modulated ones. In combination with previous studies, it is expected that our results could lead to the realization of ootimum designs for plasmonic nanolenses.展开更多
The present paper describes the ashing and atomization processes in silicon analysis by electrothermally atomised atomic absorption spectrometry(EAAAS) with an uncoat-ed graphite tube, a pyrolytically coated graphite ...The present paper describes the ashing and atomization processes in silicon analysis by electrothermally atomised atomic absorption spectrometry(EAAAS) with an uncoat-ed graphite tube, a pyrolytically coated graphite tube and a tungsten-coated graphitetube. The sensitivity and linear range of three graphite tubes were compared. By using optical temperature control accessory, the signals are enhanced by a factor of 2 and the germanium interferences in the determination of silicon are eliminated. The effects of time constant and carrier gas flow-rate on the determination of silicon were also tested. The sample can be directly analyzed in its aqueous solution without any pretreatment. The measurements of samples containing 0. 2 μg/mL and 0. 4 μg/mL silicon were run ten times and the variation coefficient is 4. 9% and 2.6%, respectively. The recovery tests for carboxyethyl germanium sesquioxide(Ge-132) synthesized and imported were performed, and the recoveries are 97. 0% and 110%, respectively. Keywords Carboxyethyl germanium sesquioxide, Electrothermally atomised atomic absorption spectrometry, Silicon展开更多
A reconfigurable metasurface based on optical control provides a control paradigm for integrating multiple functions at the same aperture,which effectively expands the freedom of control.However,the traditional light ...A reconfigurable metasurface based on optical control provides a control paradigm for integrating multiple functions at the same aperture,which effectively expands the freedom of control.However,the traditional light control method requires the light source to directly illuminate the photosensitive device,which forces the metasurface to be placed only according to the light emitter position,and even to need to be integrated on the light emitter,limiting the application scenarios of light-controlled reconfigurable metasurfaces.In this work,a light control method based on optical fiber is proposed,which guides and controls the light propagation path through optical fiber.The metasurface can be flexibly deployed,breaking through the limitation of physical space.As a verification,photoresistors are embedded in the metasurface,and the active device is directly excited by the light source as a driving signal to realize the switching of a polarization conversion function.The experimental results show that the optical-fiber-controlled metasurface can achieve linear-to-linear polarization conversion in the light environment and linear-to-circular polarization conversion in the dark environment.This work paves a new way,to our knowledge,to achieve a light-controlled metasurface,which enriches the family of intelligent metasurfaces and has great potential in many fields.展开更多
A state equation for radical 4-degree-of-freedom active magnetic bearings isbuilt, and the approach on how to use linear quadratic method of optical control theory to design acentralized and decentralized parameters c...A state equation for radical 4-degree-of-freedom active magnetic bearings isbuilt, and the approach on how to use linear quadratic method of optical control theory to design acentralized and decentralized parameters control system is introduced, and also Matlab language isused to simulate and analyze. The simulation results have proved that the differences are smallbetween centralized parameters and decentralized parameters control system. The conclusions ofexperiments have shown that decentralized controllers designed from optimal state feedback theorymeet the requirements of active magnetic bearing system. The vibration amplitude of the rotor isabout 20 mu m when the speed of the rotor runs between 0 to 60 000 r/min. This method may be used inthe study and design of controllers of magnetic bearings.展开更多
Integrated optoelectronic chips working in the visible spectrum range have promising applications in augmented reality and virtual reality,quantum information processing,biosensors,and more.A silicon nitride optical p...Integrated optoelectronic chips working in the visible spectrum range have promising applications in augmented reality and virtual reality,quantum information processing,biosensors,and more.A silicon nitride optical phased array(OPA)can shape and steer light to enable these applications on a compact chip without moving parts.However,smaller wavelength,waveguide size,and the thermo-optic coefficient pose challenges in processing,calibration,and control of silicon nitride OPA chips.In this work,a high-speed phase control system for 532 nm silicon nitride OPA,utilizing a field programmable gate array and a digital-to-analog converter,achieves a 7.4μs voltage configuration.With this system,the single-shot multivoltage optimization of beam calibration of the OPA for tens of milliseconds is realized,and the beam scanning in the range of ±24° is demonstrated.The system fully meets the needs of high-speed scanning of silicon nitride OPA,advancing OPA's development and applications.展开更多
Significant optical engineering advances at the University of Arizona are being made for design, fabrication, and construction of next generation astronomical telescopes. This summary review paper focuses on the techn...Significant optical engineering advances at the University of Arizona are being made for design, fabrication, and construction of next generation astronomical telescopes. This summary review paper focuses on the technological advances in three key areas. First is the optical fabrication technique used for constructing next-generation telescope mirrors. Advances in ground-based telescope control and instrumentation comprise the second area of development. This includes active alignment of the laser truss-based Large Binocular Telescope(LBT) prime focus camera, the new MOBIUS modular cross-dispersion spectroscopy unit used at the prime focal plane of the LBT, and topological pupil segment optimization. Lastly, future space telescope concepts and enabling technologies are discussed. Among these, the Nautilus space observatory requires challenging alignment of segmented multi-order diffractive elements. The OASIS terahertz space telescope presents unique challenges for characterizing the inflatable primary mirror, and the Hyperion space telescope pushes the limits of high spectral resolution, far-UV spectroscopy. The Coronagraphic Debris and Exoplanet Exploring Pioneer(CDEEP) is a Small Satellite(Small Sat) mission concept for high-contrast imaging of circumstellar disks and exoplanets using vector vortex coronagraph. These advances in optical engineering technologies will help mankind to probe, explore, and understand the scientific beauty of our universe.展开更多
Transition-metal oxides have attracted much attention due to its abundant crystalline phases and intriguing physical properties. However, some of these compounds are difficult to be fabricated directly in film form du...Transition-metal oxides have attracted much attention due to its abundant crystalline phases and intriguing physical properties. However, some of these compounds are difficult to be fabricated directly in film form due to the ease of valence variation of transition-metal elements.In this work, we reveal the reversible structural transition between SrVO3 and Sr2V2O7 films via thermal treatment in oxygen atmosphere or in vacuum. Based on this, Sr2V2O7 epitaxial films are successfully synthesized and studied. Property characterizations show that the semitransparent and metallic SrVO3 could reversibly switch into transparent and insulating Sr2V2O7, implying potential applications in controllable electronic and optical devices.展开更多
In this letter a Monte Carlo(MC) algorithm is used to simulate the propagation of polarized light in double-layer turbid media and the 2-dimentional backscattered Stokes vectors and Mueller matrices are obtained.Relat...In this letter a Monte Carlo(MC) algorithm is used to simulate the propagation of polarized light in double-layer turbid media and the 2-dimentional backscattered Stokes vectors and Mueller matrices are obtained.Relationships between backscattered Mueller matrix and optical properties,such as scattering,absorption and layered structure,are discussed in detail.Integrating the 2-dimentional Mueller matrix elements along radial and azimuthal directions,we obtain a reverse trend with respect to the optical parameters for upper and lower layers,which suggests possibilities for discriminating subtle optical properties in a double-layer structure using backscattered polarization patterns such as Mueller matrix.展开更多
We present a method of realizing anticontrol chaos in a quantum confined system consisting of N two-levelatoms within a cavity, using a time-delayed optic field. The delay time plays a construction and organization ro...We present a method of realizing anticontrol chaos in a quantum confined system consisting of N two-levelatoms within a cavity, using a time-delayed optic field. The delay time plays a construction and organization role forproducing temporal chaos, while the interaction between atoms and photons creates spatial chaos. The chaos is quitesensitive to small time delayed. The spectral decomposition of the Hamiltonian obtained by using projection methodologyreveals that evolution of the left eigenvectors shows quite complicated chaotic fashions. The method we proposed maybe easily tested in experiment, and provides a general method using a sort of driving optic field to achieve anticontrol ofchaos for quantum systems.展开更多
Based on a media access and control(MAC)protocol,an arrangement of channels and transceivers in optical packet switching dense wavelength division multiplexing(DWDM)networks is proposed in this paper.In order to r...Based on a media access and control(MAC)protocol,an arrangement of channels and transceivers in optical packet switching dense wavelength division multiplexing(DWDM)networks is proposed in this paper.In order to reduce the cost of nodes,fixed transmitters and receivers are used instead of tunable transmitters and receivers.Two fixed transmitters and many fixed receivers are used in each node in the scheme.The average waiting delay of this scheme is analyzed through mathematics and computer simulation.The result shows that the property of the scheme is almost the same as using tunable transmitter and receiver.Furthermore,if the tuning time of tunable transmitters is taken into account,the performance of the tunable transmitter scheme is poor than this scheme at the average waiting delay and throughput of the network.展开更多
The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precis...The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precision control.Establishing one spacecraftwith two laser links,compared to one spacecraft with a single laser link,requires an upgraded decoupling algorithmfor the link establishment.The decoupling algorithmwe designed reassigns the degrees of freedomand forces in the control loop to ensure sufficient degrees of freedomfor optical axis control.In addressing the distinct dynamic characteristics of different degrees of freedom,a transfer function compensation method is used in the decoupling process to further minimize motion coupling.The open-loop frequency response of the systemis obtained through simulation.The upgraded decoupling algorithms effectively reduce the open-loop frequency response by 30 dB.The transfer function compensation method efficiently suppresses the coupling of low-frequency noise.展开更多
The precise control of optical polarization states has emerged as a cornerstone of photonic engineering,underpinning information encoding,optical processing systems,and quantum stateresolved transmission protocols[1-3...The precise control of optical polarization states has emerged as a cornerstone of photonic engineering,underpinning information encoding,optical processing systems,and quantum stateresolved transmission protocols[1-3].Birefringent crystals exhibit optical anisotropy owing to distinct refractive indices along crystallographic axes,thereby distinguishing them from isotropic optical materials.展开更多
Invasive fungal infections(IFIs)have been associated with high mortality,highlighting the urgent need for developing novel antifungal strategies.Herein the first light-responsive antifungal agents were designed by opt...Invasive fungal infections(IFIs)have been associated with high mortality,highlighting the urgent need for developing novel antifungal strategies.Herein the first light-responsive antifungal agents were designed by optical control of fungal ergosterol biosynthesis pathway with photocaged triazole lanosterol 14a-demethylase(CYP51)inhibitors.The photocaged triazoles completely shielded the CYP51inhibition.The content of ergosterol in fungi before photoactivation and after photoactivation was 4.4%and 83.7%,respectively.Importantly,the shielded antifungal activity(MIC80≥64μg/m L)could be efficiently recovered(MIC80=0.5—8μg/m L)by light irradiation.The new chemical tools enable optical control of fungal growth arrest,morphological conversion and biofilm formation.The ability for highprecision antifungal treatment was validated by in vivo models.The light-activated compound A1 was comparable to fluconazole in prolonging survival in Galleria mellonella larvae with a median survival of 14 days and reducing fungal burden in the mouse skin infection model.Overall,this study paves the way for precise regulation of antifungal therapy with improved efficacy and safety.展开更多
We have delivered viral vectors containing either Chop2 fused with GFP, Channelrhodopsin-2 (ChR2), or Halorhodopsin (HaloR) fused with mCherry (to form light gated cation channels or chloride pumps, respectively...We have delivered viral vectors containing either Chop2 fused with GFP, Channelrhodopsin-2 (ChR2), or Halorhodopsin (HaloR) fused with mCherry (to form light gated cation channels or chloride pumps, respectively), into the dorsal cochlear nucleus (DCN). One to eighteen months later we examined the CN and inferior colliculus (IC) for evidence of virally transfected cells and processes. Production of ChR2 and HaloR was observed throughout the DCN. Rhodopsin localization within neurons was determined, with elongate, fusiform and giant cells identified based on morphology and location within the DCN. Production of ChR2 and HaloR was found at both the injection site as well as in regions projecting to and from the DCN. Light driven neuronal activity in the DCN was dependent upon the wavelength and intensity of the light, with only the appropriate wavelength resulting in activation and higher intensity light resulting in more neuronal activity. Transfecting cells via viral delivery of rhodopsins can be useful as a tract tracer and as a neuronal marker to delineate pathways. In the future rhodopsin delivery and activation may be developed as an alternative to electrical stimulation of neurons.展开更多
基金supported in part by the National Natural Science Foundation of China(NSFC)(grant number 52375534,52175503,and 51975179)the National Key Research and Development Program of China(grant number 2019YFE010747)the Fundamental Research Funds for the Central Universities(JZ2024HGTG0306).
文摘Dissipative Kerr solitons in optical microcavities enable various stable states involving multi-soliton and perfect soliton crystal(PSC),leading to widespread applications.However,the triggering condition and switching dynamics of the PSC and multi-soliton states(MSs)remain unexplored,which makes it challenging to selectively trigger the PSC/MS state for distinct area.Here,we theoretically and experimentally investigate the realization and switching of multi-/single-soliton and PSC states by engineering the periodic intracavity potential field constructed by control laser in a high-Q microrod cavity.We show that,by varying the parameters of the control laser,the PSC and multi-/single-soliton states can be selectively excited,and the soliton dynamics depends on the chaotic regime.We establish a fundamental link between the PSC switching behavior with the transient chaotic regime.Using such relation,we also demonstrate the switching and dynamical phenomena involving the conversion between PSC and MS,and soliton crystal melting and recrystallization.Our work provides additional routes for manipulation of soliton temporal and spectral profiles in optical microcavity systems and enables soliton generation on demand with desired states inside a single device.
基金Research reported in this publication was supported in part by the NSF and SC EPSCoR/IDeA Program under NSF Award#OIA-1655740(GEAR CRP 20-GC02,23-GC01)and NSF Award No.2030128,2110033supported in part by the US Department of Energy,Office of Science,Office of Workforce Development for Teachers and Scientists(WDTS)under the Visiting Faculty Program(VFP)+1 种基金support from the Air Force Office of Scientific Research under Award No.FA9550-22-1-0349 and National Science Foundation under Award No.DMR-2326944 and No.DMR-2340773the support from the program of Educational Department of Liaoning Province(grant no.LQGD2020008).
文摘Optical control of magnons in two-dimensional(2D)materials promises new functionalities for spintronics and magnonics in atomically thin devices.Here,we report control of magnon dynamics,using laser polarization,in a ferromagnetic van der Waals(vdW)material,Fe3.6Co1.4GeTe2.The magnon amplitude,frequency,and lifetime are controlled and monitored by time-resolved pump-probe spectroscopy.We show substantial(over 25%)and continuous modulation of magnon dynamics as a function of incident laser polarization.Our results suggest that the modification of the effective demagnetization field and magnetic anisotropy by the pump laser pulses with different polarizations is due to anisotropic optical absorption.This implies that pump laser pulses modify the local spin environment,which enables the launch of magnons with tunable dynamics.Our first-principles calculations confirm the anisotropic optical absorption of different crystal orientations.Our findings suggest a new route for the development of opto-spintronic or opto-magnonic devices.
基金supported by the Fundamental Research Funds for the Central Universities(108-4115100092)the National Key Research and Development Program of China(2016YFA0300102 and 2017YFA0205004)+2 种基金the National Natural Science Foundation of China(11775224,11504358,11804324 and 52072102)the Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology(2018CXFX001)the Natural Science Research Projects for the Colleges and Universities of Anhui Province(KJ2018A0660)。
文摘Optical control of exotic properties in strongly correlated electron materials is very attractive owing to their potential applications in optical and electronic devices.Herein,we demonstrate a vertical heterojunction made of a correlated electron oxide thin film VO_(2) and a conductive 0.05 wt% Nb-doped TiO_(2) single crystal,whose metal-insulator transition(MIT)across the nanoscale heterointerface can be efficiently modulated by visible light irradiation.The magnitude of the MIT decreases from ~350 in the dark state to ~7 in the illuminated state,obeying a power law with respect to the light power density.The junction resistance is switched in a reversible and synchronous manner by turning light on and off.The optical tunability of it is also exponentially proportional to the light power density,and a 320-fold on/off ratio is achieved with an irradiance of 65.6 mW cm^(-2) below the MIT temperature.While the VO_(2) thin film is metallic above the MIT temperature,the optical tunability is remarkably weakened,with a one-fold change remaining under light illumination.These results are co-attributed to a net reduction(~15 meV)in the apparent barrier height and the photocarrier-injection-induced metallization of the VO_(2) heterointerface through a photovoltaic effect,which is induced by deep defect level transition upon the visible light irradiance at low temperature.Additionally,the optical tunability is minimal,resulting from the quite weak modulation of the already metallic band structure in the Schottky-type junction above the MIT temperature.This work enables a remotely optical scheme to manipulate the MIT,implying potential uncooled photodetection and photoswitch applications.
基金This work was financially supported by National Natural Science Foundation of China(92253301,U22A20332,92156025,and 21922701)the National Key Research and Development Program of China(2022YFA0912403 and 2021YFA0909900)+1 种基金the Beijing Natural Science Foundation(JQ20034)to T.L and Peking UniversityInnovation Fund for Outstanding Doctoral Candidates of Peking University Health Science Center(71006Y2460)to X.L.
文摘Genetic encoding of photocaged noncanonical amino acids provides a powerful tool to study protein functions through optical control but is not yet available for acidic amino acids.Herein,we report the first site-specific genetic encoding of a photocaged glutamate,4-methoxy-7-nitroindolinyl caged glutamate(MNI-Glu),into recombinant proteins via an expanded genetic code through evolved EcLeuRS/tRNA pair.Using two enzymes as examples,we demonstrate that substituting the conserved-active-site glutamate of a secreted alkaline phosphatase and a protease HRV3C to MNI-Glu allows photoregulatory control of their enzymatic activities.Our approach is an important addition to the photocaged noncanonical amino-acid toolbox and provides a general method to photocontrol protein activity based on caging a critical glutamate.
基金supported by National Natural Science Foundation of China(No.61571061)Innovative Research Fund of Beijing University of Posts and Telecommunications (2015RC16)
文摘The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features such as rapid provisioning,automated protection and restoration(P&R),efficient resource allocation,and support for different quality of service(QoS) requirements.In this paper,we propose a novel stateful PCE-cloud(SPC)based architecture of GMPLS optical networks for cloud services.The cloud computing technologies(e.g.virtualization and parallel computing) are applied to the construction of SPC for improving the reliability and maximizing resource utilization.The functions of SPC and GMPLS based control plane are expanded according to the features of cloud services for different QoS requirements.The architecture and detailed description of the components of SPC are provided.Different potential cooperation relationships between public stateful PCE cloud(PSPC) and region stateful PCE cloud(RSPC) are investigated.Moreover,we present the policy-enabled and constraint-based routing scheme base on the cooperation of PSPC and RSPC.Simulation results for verifying the performance of routing and control plane reliability are analyzed.
文摘We theoretically analyze the transient properties of a probe field absorption and dispersion in a coupled semiconductor double-quantum-dot nanostructure.We show that in the presence of the Gaussian laser beams,absorption and dispersion of the probe field can be dramatically influenced by the relative phase between applied fields and intensity of the Gaussian laser beams.Transient and steady-state behaviors of the probe field absorption and dispersion are discussed to estimate the required switching time.The estimated range is between 5-8 ps for subluminal to superluminal light propagation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61203211 and 20907021)the Foundation for Outstanding Young Teachers of Nanjing University of Information Science&Technology,China(Grant No.20110423)
文摘A technique capable of focusing and bending electromagnetic (EM) waves through plasmonic gratings with equally spaced alternately tapered slits has been introduced. Phase resonances are observed in the optical response of transmission gratings, and the EM wave passes through the tuning slits in the form of surface plasmon polaritons (SPPs) and obtains the required phase retardation to focus at the focal plane. The bending effect is achieved by constructing an asymmetric phase front which results from the tapered slits and gradient refractive index (GRIN) distribution of the dielectric material. Rigorous electromagnetic analysis by using the two-dimensional (2D) finite difference time domain (FDTD) method is employed to verify our proposed designs. When the EM waves are incident at an angle on the optical axis, the beam splitting effect can also be achieved. These index-modulated slits are demonstrated to have unique advantages in beam manipulation compared with the width-modulated ones. In combination with previous studies, it is expected that our results could lead to the realization of ootimum designs for plasmonic nanolenses.
文摘The present paper describes the ashing and atomization processes in silicon analysis by electrothermally atomised atomic absorption spectrometry(EAAAS) with an uncoat-ed graphite tube, a pyrolytically coated graphite tube and a tungsten-coated graphitetube. The sensitivity and linear range of three graphite tubes were compared. By using optical temperature control accessory, the signals are enhanced by a factor of 2 and the germanium interferences in the determination of silicon are eliminated. The effects of time constant and carrier gas flow-rate on the determination of silicon were also tested. The sample can be directly analyzed in its aqueous solution without any pretreatment. The measurements of samples containing 0. 2 μg/mL and 0. 4 μg/mL silicon were run ten times and the variation coefficient is 4. 9% and 2.6%, respectively. The recovery tests for carboxyethyl germanium sesquioxide(Ge-132) synthesized and imported were performed, and the recoveries are 97. 0% and 110%, respectively. Keywords Carboxyethyl germanium sesquioxide, Electrothermally atomised atomic absorption spectrometry, Silicon
基金National Key Research and Development Program of China(2022YFB3806200)National Natural Science Foundation of China(62201609,62401614,62401617)。
文摘A reconfigurable metasurface based on optical control provides a control paradigm for integrating multiple functions at the same aperture,which effectively expands the freedom of control.However,the traditional light control method requires the light source to directly illuminate the photosensitive device,which forces the metasurface to be placed only according to the light emitter position,and even to need to be integrated on the light emitter,limiting the application scenarios of light-controlled reconfigurable metasurfaces.In this work,a light control method based on optical fiber is proposed,which guides and controls the light propagation path through optical fiber.The metasurface can be flexibly deployed,breaking through the limitation of physical space.As a verification,photoresistors are embedded in the metasurface,and the active device is directly excited by the light source as a driving signal to realize the switching of a polarization conversion function.The experimental results show that the optical-fiber-controlled metasurface can achieve linear-to-linear polarization conversion in the light environment and linear-to-circular polarization conversion in the dark environment.This work paves a new way,to our knowledge,to achieve a light-controlled metasurface,which enriches the family of intelligent metasurfaces and has great potential in many fields.
基金This project is supported by Aeronautic Science Foundation (No.98C52052) National Natural Science Foundation of China (No.50275067, No.60174052).
文摘A state equation for radical 4-degree-of-freedom active magnetic bearings isbuilt, and the approach on how to use linear quadratic method of optical control theory to design acentralized and decentralized parameters control system is introduced, and also Matlab language isused to simulate and analyze. The simulation results have proved that the differences are smallbetween centralized parameters and decentralized parameters control system. The conclusions ofexperiments have shown that decentralized controllers designed from optimal state feedback theorymeet the requirements of active magnetic bearing system. The vibration amplitude of the rotor isabout 20 mu m when the speed of the rotor runs between 0 to 60 000 r/min. This method may be used inthe study and design of controllers of magnetic bearings.
基金supported by the National Natural Science Foundation of China(Nos.62335019 and 61975243)。
文摘Integrated optoelectronic chips working in the visible spectrum range have promising applications in augmented reality and virtual reality,quantum information processing,biosensors,and more.A silicon nitride optical phased array(OPA)can shape and steer light to enable these applications on a compact chip without moving parts.However,smaller wavelength,waveguide size,and the thermo-optic coefficient pose challenges in processing,calibration,and control of silicon nitride OPA chips.In this work,a high-speed phase control system for 532 nm silicon nitride OPA,utilizing a field programmable gate array and a digital-to-analog converter,achieves a 7.4μs voltage configuration.With this system,the single-shot multivoltage optimization of beam calibration of the OPA for tens of milliseconds is realized,and the beam scanning in the range of ±24° is demonstrated.The system fully meets the needs of high-speed scanning of silicon nitride OPA,advancing OPA's development and applications.
基金the Gordon and Betty Moore Foundation for their financial support of the development of the MODElens and its enabling alignment technologiesthe II-VI Foundation Block-Gift,Technology Research Initiative Fund Optics/Imaging Program。
文摘Significant optical engineering advances at the University of Arizona are being made for design, fabrication, and construction of next generation astronomical telescopes. This summary review paper focuses on the technological advances in three key areas. First is the optical fabrication technique used for constructing next-generation telescope mirrors. Advances in ground-based telescope control and instrumentation comprise the second area of development. This includes active alignment of the laser truss-based Large Binocular Telescope(LBT) prime focus camera, the new MOBIUS modular cross-dispersion spectroscopy unit used at the prime focal plane of the LBT, and topological pupil segment optimization. Lastly, future space telescope concepts and enabling technologies are discussed. Among these, the Nautilus space observatory requires challenging alignment of segmented multi-order diffractive elements. The OASIS terahertz space telescope presents unique challenges for characterizing the inflatable primary mirror, and the Hyperion space telescope pushes the limits of high spectral resolution, far-UV spectroscopy. The Coronagraphic Debris and Exoplanet Exploring Pioneer(CDEEP) is a Small Satellite(Small Sat) mission concept for high-contrast imaging of circumstellar disks and exoplanets using vector vortex coronagraph. These advances in optical engineering technologies will help mankind to probe, explore, and understand the scientific beauty of our universe.
基金supported by the National Key R&D Program of China(No.2016YFA0300102)the National Natural Science Foundation of China(No.11675179,No.11434009,and No.11374010)+2 种基金the Fundamental Research Funds for the Central Universities(No.WK2340000065)partially carried out at the University of Science and Technology of China(USTC)center for Micro and Nanoscale Research and Fabricationthe support from the magnetic circular dichroism endstation at Hefei Light Source
文摘Transition-metal oxides have attracted much attention due to its abundant crystalline phases and intriguing physical properties. However, some of these compounds are difficult to be fabricated directly in film form due to the ease of valence variation of transition-metal elements.In this work, we reveal the reversible structural transition between SrVO3 and Sr2V2O7 films via thermal treatment in oxygen atmosphere or in vacuum. Based on this, Sr2V2O7 epitaxial films are successfully synthesized and studied. Property characterizations show that the semitransparent and metallic SrVO3 could reversibly switch into transparent and insulating Sr2V2O7, implying potential applications in controllable electronic and optical devices.
基金supported by the Governmental Education Bureau of Fujian Province(No.JA10068)the 2009 Project for Scientific and Technical Development of Xiamen (No.3502Z20099007)
文摘In this letter a Monte Carlo(MC) algorithm is used to simulate the propagation of polarized light in double-layer turbid media and the 2-dimentional backscattered Stokes vectors and Mueller matrices are obtained.Relationships between backscattered Mueller matrix and optical properties,such as scattering,absorption and layered structure,are discussed in detail.Integrating the 2-dimentional Mueller matrix elements along radial and azimuthal directions,we obtain a reverse trend with respect to the optical parameters for upper and lower layers,which suggests possibilities for discriminating subtle optical properties in a double-layer structure using backscattered polarization patterns such as Mueller matrix.
文摘We present a method of realizing anticontrol chaos in a quantum confined system consisting of N two-levelatoms within a cavity, using a time-delayed optic field. The delay time plays a construction and organization role forproducing temporal chaos, while the interaction between atoms and photons creates spatial chaos. The chaos is quitesensitive to small time delayed. The spectral decomposition of the Hamiltonian obtained by using projection methodologyreveals that evolution of the left eigenvectors shows quite complicated chaotic fashions. The method we proposed maybe easily tested in experiment, and provides a general method using a sort of driving optic field to achieve anticontrol ofchaos for quantum systems.
文摘Based on a media access and control(MAC)protocol,an arrangement of channels and transceivers in optical packet switching dense wavelength division multiplexing(DWDM)networks is proposed in this paper.In order to reduce the cost of nodes,fixed transmitters and receivers are used instead of tunable transmitters and receivers.Two fixed transmitters and many fixed receivers are used in each node in the scheme.The average waiting delay of this scheme is analyzed through mathematics and computer simulation.The result shows that the property of the scheme is almost the same as using tunable transmitter and receiver.Furthermore,if the tuning time of tunable transmitters is taken into account,the performance of the tunable transmitter scheme is poor than this scheme at the average waiting delay and throughput of the network.
基金supported by the National Key Research and Development Program of China(2022YFC2203700).
文摘The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precision control.Establishing one spacecraftwith two laser links,compared to one spacecraft with a single laser link,requires an upgraded decoupling algorithmfor the link establishment.The decoupling algorithmwe designed reassigns the degrees of freedomand forces in the control loop to ensure sufficient degrees of freedomfor optical axis control.In addressing the distinct dynamic characteristics of different degrees of freedom,a transfer function compensation method is used in the decoupling process to further minimize motion coupling.The open-loop frequency response of the systemis obtained through simulation.The upgraded decoupling algorithms effectively reduce the open-loop frequency response by 30 dB.The transfer function compensation method efficiently suppresses the coupling of low-frequency noise.
基金supported by the National Key Research and Development Program of China(2021YFB3601502)National Natural Science Foundation of China(22193044,22361132544,22335007,52172012)+5 种基金CAS Project for Young Scientists in Basic Research(YSBR-024)Xinjiang Major Science and Technology Project(2021A01001)Tianshan Talent Project(2022TSYCJU0001,2022TSYCCX0078)Xinjiang University 2024 Outstanding Doctoral Students’Innovation Project(XJU2024BS053)Postdoctoral Fellow-Ship Program(Grade C)(GZC20232959)Tianchi Talent Program of Xinjiang Uygur Autonomous Region。
文摘The precise control of optical polarization states has emerged as a cornerstone of photonic engineering,underpinning information encoding,optical processing systems,and quantum stateresolved transmission protocols[1-3].Birefringent crystals exhibit optical anisotropy owing to distinct refractive indices along crystallographic axes,thereby distinguishing them from isotropic optical materials.
基金supported by the National Natural Science Foundation(81725020,82003591 and 81973175,China)the Innovation Program of Shanghai Municipal Education Commission(2019-01-07-00-07-E00073,China)Science and Technology Commission of Shanghai Municipality(20S11900400,China)。
文摘Invasive fungal infections(IFIs)have been associated with high mortality,highlighting the urgent need for developing novel antifungal strategies.Herein the first light-responsive antifungal agents were designed by optical control of fungal ergosterol biosynthesis pathway with photocaged triazole lanosterol 14a-demethylase(CYP51)inhibitors.The photocaged triazoles completely shielded the CYP51inhibition.The content of ergosterol in fungi before photoactivation and after photoactivation was 4.4%and 83.7%,respectively.Importantly,the shielded antifungal activity(MIC80≥64μg/m L)could be efficiently recovered(MIC80=0.5—8μg/m L)by light irradiation.The new chemical tools enable optical control of fungal growth arrest,morphological conversion and biofilm formation.The ability for highprecision antifungal treatment was validated by in vivo models.The light-activated compound A1 was comparable to fluconazole in prolonging survival in Galleria mellonella larvae with a median survival of 14 days and reducing fungal burden in the mouse skin infection model.Overall,this study paves the way for precise regulation of antifungal therapy with improved efficacy and safety.
基金supported by Ralph Wilson Foundation(to A.G.H)Capita Foundation(to A.G.H)
文摘We have delivered viral vectors containing either Chop2 fused with GFP, Channelrhodopsin-2 (ChR2), or Halorhodopsin (HaloR) fused with mCherry (to form light gated cation channels or chloride pumps, respectively), into the dorsal cochlear nucleus (DCN). One to eighteen months later we examined the CN and inferior colliculus (IC) for evidence of virally transfected cells and processes. Production of ChR2 and HaloR was observed throughout the DCN. Rhodopsin localization within neurons was determined, with elongate, fusiform and giant cells identified based on morphology and location within the DCN. Production of ChR2 and HaloR was found at both the injection site as well as in regions projecting to and from the DCN. Light driven neuronal activity in the DCN was dependent upon the wavelength and intensity of the light, with only the appropriate wavelength resulting in activation and higher intensity light resulting in more neuronal activity. Transfecting cells via viral delivery of rhodopsins can be useful as a tract tracer and as a neuronal marker to delineate pathways. In the future rhodopsin delivery and activation may be developed as an alternative to electrical stimulation of neurons.