Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to ethylene(C_(2)H_(4))represents a promising approach to reducing CO_(2)emissions and producing high-value chemicals.The ethylene productivity is always limited by t...Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to ethylene(C_(2)H_(4))represents a promising approach to reducing CO_(2)emissions and producing high-value chemicals.The ethylene productivity is always limited by the slow reaction kinetics and the high-performance catalysts are significantly desired.Many efforts have been made to develop a catalyst to activate CO_(2)molecules.However,as another reactant,H2O activation does not receive the attention it deserves.In particular,slow H2O dissociation kinetics limit the rate of proton supply,severely impairing the production of C_(2)H_(4).Here,we designed a MgO-modified CuO catalyst(MgO/CuO),which can promote H2O dissociation and enhance CO_(2)adsorption at the same time to realize the efficient ethylene production.The optimal catalyst exhibits a Faraday efficiency for C_(2)H_(4)reached 54.4%at−1.4 V vs.RHE in an H-cell,which is 1.4 times that of pure CuO(37.9%),and it was further enhanced to a 56.7%in a flow cell,with a high current density of up to 535.9 mA cm−2 at−1.0 V vs.RHE.Experimental and theoretical calculations show that MgO/CuO plays a bifunctional role in the CO_(2)RR,which facilitates the adsorption and activation of CO_(2)by CuO and simultaneously accelerates H2O dissociation by MgO doping.The in situ XRD experiments demonstrate that the introduction of MgO protects CuO active phase to avoid overreduction and preserves the active centers for CO_(2)RR.In combination with in situ FTIR and DFT calculations,the protonation process from*CO to*COH and asymmetric C–C coupling step are promoted by the enhanced water activation and proton coupling on MgO/CuO.This work provides new insights into the CO_(2)and H_(2)O coactivation mechanism in CO_(2)RR and a potential universal strategy to design ethylene production electrocatalysts.展开更多
In ghost imaging, an illumination light is split into test and reference beams which pass through two different optical systems respectively and an image is constructed with the second-order correlation between the tw...In ghost imaging, an illumination light is split into test and reference beams which pass through two different optical systems respectively and an image is constructed with the second-order correlation between the two light beams. Since both light beams are diffracted when passing through the optical systems, the spatial resolution of ghost imaging is in general lower than that of a corresponding conventional imaging system. When Gaussian-shaped light spots are used to illuminate an object, randomly scanning across the object plane, in the ghost imaging scheme, we show th√at by localizing central positions of the spots of the reference light beam, the resolution can be increased by a factor of 2^(1/2) same as that of the corresponding conventional imaging system. We also find that the resolution can be further enhanced by setting an appropriate threshold to the bucket measurement of ghost imaging.展开更多
The combination of a powerful CO_(2)-enriching carrier and robust active component provides a new idea for the construction of efficient catalysts for electrocatalytic CO_(2)reduction.Herein,novel perforated nitrogen-...The combination of a powerful CO_(2)-enriching carrier and robust active component provides a new idea for the construction of efficient catalysts for electrocatalytic CO_(2)reduction.Herein,novel perforated nitrogen-rich graphene-like carbon nanolayers(PNGC)are prepared from biomass derivatives,which promotes the oriented deposition of In-doped Cu_(2)(OH)_(3)(NO_(3))nanosheet patches.A robust Cu-In/PNGC composite catalyst is then obtained via simple in-situ electrochemical reduction.Unsurprisingly,CuIn/PNGC exhibits a CO Faradaic efficiency(FECO)of 91.3%and a remarkable CO partial current density(jCO)of 136.4 m A cm^(-2)at a moderate overpotential of 0.59 V for electrocatalytic CO_(2)reduction reaction(CO_(2)RR).DFT calculations and experimental studies indicate that the strong carrier effect of PNGC makes PNGC carried Cu-In nanosheets improved the adsorption capacity of CO_(2)gas,reconfigured electronic structure,and reduced free energy of key intermediate formation,thereby the CO_(2)activation and conversion are promoted.展开更多
Photonic multi-dimensional storage capabilities and the high storage efficiency of multiplexed quantum storage devices are critical metrics that directly determine the entanglement distribution efficiency of quantum n...Photonic multi-dimensional storage capabilities and the high storage efficiency of multiplexed quantum storage devices are critical metrics that directly determine the entanglement distribution efficiency of quantum networks.展开更多
The heavy metal pollution in water,largely driven by human activities,has become a significant concern in China.Pyrite has gained attention for treating heavy metal wastewater due to its excellent adsorptive and redox...The heavy metal pollution in water,largely driven by human activities,has become a significant concern in China.Pyrite has gained attention for treating heavy metal wastewater due to its excellent adsorptive and redox properties,affordability,and environmental compatibility.However,the inherent limitations of natural pyrite,such as its small specific surface area,inadequate active sites,and tendency to agglomerate,hinder its effectiveness in removing heavy metal ions.To address these shortcomings and optimize pyrite’s performance in practical applications,various modification strategies have been developed.In this paper,the oxidation,reduction,and adsorption capabilities of pyrite with respect to different heavy metal ions have been systematically reviewed by the comparison of the underlying mechanisms.We also discussed pyrite modification strategies and their corresponding enhancement mechanisms.Finally,the paper systematically reviews the current application status and future research trends of pyrite and its modified composites in heavy metal wastewater treatment.Basically,this work provides a systematic review on pyrite-based materials for heavy metal removal,from theoretical insights to practical applications and future modification strategies.展开更多
The quantum eraser effect exemplifies the distinctive properties of quantum mechanics that challenge classical intuition and reveal the wave-particle duality of light.Whether the photon exhibits particle-like or wave-...The quantum eraser effect exemplifies the distinctive properties of quantum mechanics that challenge classical intuition and reveal the wave-particle duality of light.Whether the photon exhibits particle-like or wave-like behavior depends on whether the path information is discernible.In this paper,we propose a novel quantum eraser scheme that utilizes photonic phase structures as the which-way indicator.This scheme is implemented using a Mach–Zehnder interferometer(MZI),where one arm is configured with orbital angular momentum(OAM)to establish predetermined which-way information.Consequently,at the output ports of the MZI,the photon displays particle-like characteristics when the which-way information is retained.However,the introduction of an additional spiral phase plate(SPP)to eliminate the phase structure from the output photon of the MZI unveils distinct interference patterns.This result enhances our understanding of the quantum erasure effect.展开更多
We propose and demonstrate an experimental implementation for the observation of magnetic fields from spatial features of absorption profiles in a warm atomic vapor.A radially polarized vector beam that traverses atom...We propose and demonstrate an experimental implementation for the observation of magnetic fields from spatial features of absorption profiles in a warm atomic vapor.A radially polarized vector beam that traverses atomic vapor will generate an absorption pattern with a petal-like structure by the mediation of a transverse magnetic field(TMF).The spatial absorption pattern rotates when the azimuthal angle of the TMF is changed,while its contrast decreases when the longitudinal component of the magnetic field increases.By analyzing the intensity distribution of the transmitted pattern,we can determine the magnetic field strength.Our work provides a framework for investigating 3 D magnetic field distributions based on atoms.展开更多
Cylindrical vector beams(CVBs),which possess polarization distribution of rotational symmetry on the transverse plane,can be developed in many optical technologies.Conventional methods to generate CVBs contain redunda...Cylindrical vector beams(CVBs),which possess polarization distribution of rotational symmetry on the transverse plane,can be developed in many optical technologies.Conventional methods to generate CVBs contain redundant interferometers or need to switch among diverse elements,thus being inconvenient in applications containing multiple CVBs.Here we provide a passive polarization-selective device to substitute interferometers and simplify generation setup.It is accomplished by reversing topological charges of orbital angular momentum based on a polarization-selective Gouy phase.In the process,tunable input light is the only condition to generate a CVB with arbitrary topological charges.To cover both azimuthal and radial parameters of CVBs,we express the mapping between scalar Laguerre–Gaussian light on a basic Poincaré sphere and CVB on a high-order Poincaré sphere.The proposed device simplifies the generation of CVBs enormously and thus has potential in integrated devices for both quantum and classic optical experiments.展开更多
Orbital angular momentum(OAM)-carrying beams have received extensive attention due to their high-dimensional characteristics in the context of free-space optical communication.However,accurate OAM mode recognition sti...Orbital angular momentum(OAM)-carrying beams have received extensive attention due to their high-dimensional characteristics in the context of free-space optical communication.However,accurate OAM mode recognition still suffers from reference misalignment of lateral displacement,beam waist size,and initial phase.Here we propose a deep-learning method to exquisitely recognize OAM modes under misalignment by using an alignment-free fractal multipoint interferometer.Our experiments achieve 98.35% recognizing accuracy when strong misalignment is added to hyperfine OAM modes whose Bures distance is 0.01.The maximum lateral displacement we added with respect to the perfectly on-axis beam is about±0.5 beam waist size.This work offers a superstable proposal for OAM mode recognition in the application of free-space optical communication and allows an increase of the communication capacity.展开更多
Tumor vasculature constitutes a formidable hurdle for the efficient delivery of cancer nanomedicine into tumors.The leverage of passive pathway through inter-endothelial gaps in tumor blood vessels might account for l...Tumor vasculature constitutes a formidable hurdle for the efficient delivery of cancer nanomedicine into tumors.The leverage of passive pathway through inter-endothelial gaps in tumor blood vessels might account for limited extravasation of nanomedicine into tumor microenvironment(TME).Herein,Annexin A1 antibody-installed mesoporous organosilica nanoplatforms carrying immunotherapeutics of anti-PD-L1 antibody(aPD-L1)and Indoximod are developed to target at caveolar Annexin-A1 protein of luminal endothelial cells and to trigger the active trans-endothelial transcytosis of nanomedicine mediated by caveolae.Such strategy enables rapid nanomedicine extravasation across tumor endothelium and relatively extensive accumulation in tumor interstitium.aPD-L1 and Indoximod release from aPD/IND@MON-aANN in a reduction-responsive manner and synergistically facilitate the intratumoral infiltration of cytotoxic T lymphocytes and reverse the immunosuppressive TME,thus demonstrating substantial anti-tumor efficacy in subcutaneous 4T1 breast tumors and remarkable anti-metastatic capacity to extend the survival of 4T1 tumor metastasis model.Moreover,aPD/IND@MON-aANN nanomedicine also exhibits distinct superiority over the combination therapy of free drugs to potently attenuate the progression of urethane-induced orthotopic lung cancers.Collectively,aPD/IND@MON-aANN nanoplatforms with boosted delivery efficiency via antibody-activated trans-endothelial pathway and enhanced immunotherapeutic efficacy provides perspectives for the development of cancer nanomedicines.展开更多
Vortex beams with fractional topological charge(FTC) have many special characteristics and novel applications.However, one of the obstacles for their application is the difficulty of precisely determining the FTC of f...Vortex beams with fractional topological charge(FTC) have many special characteristics and novel applications.However, one of the obstacles for their application is the difficulty of precisely determining the FTC of fractional vortex beams. We find that when a vortex beam with an FTC illuminates a dynamic angular double slit(ADS), the far-field interference patterns that include the information of the FTC of the beam at the angular bisector direction of the ADS vary periodically. Based on this property, a simple dynamic ADS device and data fitting method can be used to precisely measure the FTC of a vortex light beam with an error of less than 5%.展开更多
In this article we report on the experimental investigation of light storage for several types of diffractionfree beams(Bessel and Airy beams)and quasi-diffraction-free beams by utilizing electromagnetically induced t...In this article we report on the experimental investigation of light storage for several types of diffractionfree beams(Bessel and Airy beams)and quasi-diffraction-free beams by utilizing electromagnetically induced transparency(EIT)technique in a hot atomic gas cell.The experimental results show that the diffraction-free and quasi-diffraction-free beams have better storage performances when compared with ordinary images possessing similar spatial profiles.Meanwhile,the Bessel beams and the quasidiffraction-free images are able to maintain their spatial profiles with a long storage time while the sidelobes of the Airy beam are gradually depleted with the increment of the storage time.We quantitatively analyze the storage results and give physical explanations behind these phenomena.Furthermore,the self-healing of the retrieved diffraction-free beams is verified,signifying that their characteristics preserve well after storage.展开更多
An image undergoes a paraxial diffraction spreading when propagating in free space.The reduction of diffraction is critical for many potential applications[1-3].Recently,it has been recognized that optical diffraction...An image undergoes a paraxial diffraction spreading when propagating in free space.The reduction of diffraction is critical for many potential applications[1-3].Recently,it has been recognized that optical diffraction can be greatly suppressed or even eliminated by using atomic coherence effects[4-9].展开更多
Excessive mining and utilization fossil fuels has led to drastic environmental consequences,which will contribute to global warming and cause further climate change with severe consequences for the human population.Th...Excessive mining and utilization fossil fuels has led to drastic environmental consequences,which will contribute to global warming and cause further climate change with severe consequences for the human population.The magnitude of these challenges requires several approaches to develop sustainable alternatives for chemicals and fuels production.In this context,biological processes,mainly microbial fermentation,have gained particular interest.For example,autotrophic gas-fermenting acetogenic bacteria are capable of converting CO,CO_(2) and H_(2) into biomass and multiple metabolites through Wood-Ljungdahl pathway,which can be exploited for large-scale fermentation processes to sustainably produce bulk biochemicals and biofuels(e.g.acetate and ethanol)from syngas.Clostridium autoethanogenum is one representative of these chemoautotrophic bacteria and considered as the model for the gas fermentation.Recently,the development of synthetic biology toolbox for this strain has enabled us to study and genetically improve their metabolic capability in gas fermentation.In this review,we will summarize the recent progress involved in the understanding of physiological mechanism and strain engineering for C.autoethanogenum,and provide our perspectives on the future development about the basic biology and engineering biology of this strain.展开更多
We experimentally demonstrate the generation of customized Laguerre–Gaussian(LG)beams whose intensity maxima are localized around any desired curves.The principle is to act with appropriate algebraic functions on the...We experimentally demonstrate the generation of customized Laguerre–Gaussian(LG)beams whose intensity maxima are localized around any desired curves.The principle is to act with appropriate algebraic functions on the angular spectra of LG beams.We characterize the propagation properties of these beams and compare them with non-diffraction caustic beams possessing the same intensity profiles.The results manifest that the customized-LG beams can maintain their profiles during propagation and suffer less energy loss than the non-diffraction caustic beams,and hence are able to propagate a longer distance.Moreover,the customized-LG beam exhibits self-healing ability when parts of their bodies are blocked.This new structure beam has potential applications in areas such as optical communication,soliton routing and steering,and optical tweezing.展开更多
Nervonic acid(NA)is an important long-chain monounsaturated fatty acid found in mammalian nervous tissue.It has recently garnered research attention due to its therapeutic potential in treating psychiatric and neurode...Nervonic acid(NA)is an important long-chain monounsaturated fatty acid found in mammalian nervous tissue.It has recently garnered research attention due to its therapeutic potential in treating psychiatric and neurodegenerative disorders.In this study,we investigated the efficacy of NA in treating ischemia/reperfusion and poststroke events in a rat model.Specifically,there was significant reduction in the infarct area,cell death,and neuronal swelling after NA treatment,and the improvement in cerebral blood flow was also observed on day five after middle cerebral artery occlusion.Moreover,NA treatment led to the upregulation of brain-derived neurotrophic factors and myelin basic protein genes.NA displayed improved effects on depressive-like behavior of rats by three validated assays—the sucrose preference test,open-field test,and forced swim test.Regarding the mechanism of action,direct supplementation of NA in the brain was observed.We also observed the indirect effects of NA on the gut microbiota.Notably,the NA group gradually restored the bacterial diversity and the EGb group exhibited no impact based on observed-out analysis.We found an increase in the abundance of Blautia and Sutterella,which participated in phenylalanine metabolism.The metabolomics of plasma and brain samples revealed a decrease in the levels of phenylalanine-based amino acids,which alleviated the inhibitory effects on glutamine metabolism and promoted the recovery and signaling transmission of neurons after stroke.Altogether,our findings suggest that NA can be a viable treatment option for alleviating stroke and its associated poststroke depressive-like behaviors.展开更多
We investigate the sensitivity of the angular rotation measurement with the method of homodyne detection in SU(2) and SU(1,1) interferometers by employing orbital angular momentum(OAM). By combining a coherent beam wi...We investigate the sensitivity of the angular rotation measurement with the method of homodyne detection in SU(2) and SU(1,1) interferometers by employing orbital angular momentum(OAM). By combining a coherent beam with a vacuum beam in an SU(2) interferometer, we get the sensitivity of the angular rotation measurement as 1/(2N^(1/2)l). We can surpass the limit of the angular rotation measurement in an SU(1,1) interferometer by combining a coherent beam with a vacuum beam or a squeezed vacuum beam when the probe beam has OAM. Without injection, the sensitivity can reach 1/(2N^(1/2)l). In addition, by employing another construction of an SU(1,1) interferometer where the pump beam has OAM, with the same injection of an SU(1,1) interferometer, the sensitivity of the angular rotation measurement can be improved by a factor of 2, reaching 1/(4Nl). The results confirm the potential of this technology for precision measurements in angular rotation measurements.展开更多
A new architecture, naked-eye ghost imaging via photoelectric feedback, is developed that avoids computer algorithm processing. Instead, the proposed scheme uses a photoelectric feedback loop to first realize the corr...A new architecture, naked-eye ghost imaging via photoelectric feedback, is developed that avoids computer algorithm processing. Instead, the proposed scheme uses a photoelectric feedback loop to first realize the correlation(multiplication) process of the traditional ghost imaging system. Then, the vision persistence effect of the naked eye is exploited to implement the integral process and to generate negative images. Two kinds of feedback circuits, the digital circuit and the analog circuit, are presented that can achieve a feedback operation. Based on this design, high-contrast real-time imaging of moving objects is obtained via a special pattern-scanning architecture on a low-speed light-modulation mask.展开更多
We demonstrate the generation of non-classical photon pairs in a warm S-Rb atomic vapor （＇ell with no buffer gas or polarization preserving coatings via spontaneous four-wave mixing. We obtain the photon pairs with ...We demonstrate the generation of non-classical photon pairs in a warm S-Rb atomic vapor （＇ell with no buffer gas or polarization preserving coatings via spontaneous four-wave mixing. We obtain the photon pairs with a 1/e correlation time of 40 ns and the violation of Cauchy-Sehwartz inequality by a factor of 23 - 3. This provides a convenient and efficient method to generate photon pair sources based on an atomic ensemble.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.U21B2099,U22A20425,and 22208377)Natural Science Foundation of Shandong Province(ZR2021QE062)Fundamental Research Funds for the Central Universities,Ocean University of China(grant number 202364004)。
文摘Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to ethylene(C_(2)H_(4))represents a promising approach to reducing CO_(2)emissions and producing high-value chemicals.The ethylene productivity is always limited by the slow reaction kinetics and the high-performance catalysts are significantly desired.Many efforts have been made to develop a catalyst to activate CO_(2)molecules.However,as another reactant,H2O activation does not receive the attention it deserves.In particular,slow H2O dissociation kinetics limit the rate of proton supply,severely impairing the production of C_(2)H_(4).Here,we designed a MgO-modified CuO catalyst(MgO/CuO),which can promote H2O dissociation and enhance CO_(2)adsorption at the same time to realize the efficient ethylene production.The optimal catalyst exhibits a Faraday efficiency for C_(2)H_(4)reached 54.4%at−1.4 V vs.RHE in an H-cell,which is 1.4 times that of pure CuO(37.9%),and it was further enhanced to a 56.7%in a flow cell,with a high current density of up to 535.9 mA cm−2 at−1.0 V vs.RHE.Experimental and theoretical calculations show that MgO/CuO plays a bifunctional role in the CO_(2)RR,which facilitates the adsorption and activation of CO_(2)by CuO and simultaneously accelerates H2O dissociation by MgO doping.The in situ XRD experiments demonstrate that the introduction of MgO protects CuO active phase to avoid overreduction and preserves the active centers for CO_(2)RR.In combination with in situ FTIR and DFT calculations,the protonation process from*CO to*COH and asymmetric C–C coupling step are promoted by the enhanced water activation and proton coupling on MgO/CuO.This work provides new insights into the CO_(2)and H_(2)O coactivation mechanism in CO_(2)RR and a potential universal strategy to design ethylene production electrocatalysts.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11534008,11605126,and 11804271)the Fund from the Ministry of Science and Technology of China(Grant No.2016YFA0301404)+2 种基金the Natural Science Basic Research Plan in Shaanxi Province,China(Grant No.2017JQ1025)the Doctoral Fund of the Ministry of Education of China(Grant Nos.2016M592772 and 2018M631137)the Fundamental Research Funds for the Central Universities
文摘In ghost imaging, an illumination light is split into test and reference beams which pass through two different optical systems respectively and an image is constructed with the second-order correlation between the two light beams. Since both light beams are diffracted when passing through the optical systems, the spatial resolution of ghost imaging is in general lower than that of a corresponding conventional imaging system. When Gaussian-shaped light spots are used to illuminate an object, randomly scanning across the object plane, in the ghost imaging scheme, we show th√at by localizing central positions of the spots of the reference light beam, the resolution can be increased by a factor of 2^(1/2) same as that of the corresponding conventional imaging system. We also find that the resolution can be further enhanced by setting an appropriate threshold to the bucket measurement of ghost imaging.
基金supported by the National Natural Science Foundation of China(U21B2099)。
文摘The combination of a powerful CO_(2)-enriching carrier and robust active component provides a new idea for the construction of efficient catalysts for electrocatalytic CO_(2)reduction.Herein,novel perforated nitrogen-rich graphene-like carbon nanolayers(PNGC)are prepared from biomass derivatives,which promotes the oriented deposition of In-doped Cu_(2)(OH)_(3)(NO_(3))nanosheet patches.A robust Cu-In/PNGC composite catalyst is then obtained via simple in-situ electrochemical reduction.Unsurprisingly,CuIn/PNGC exhibits a CO Faradaic efficiency(FECO)of 91.3%and a remarkable CO partial current density(jCO)of 136.4 m A cm^(-2)at a moderate overpotential of 0.59 V for electrocatalytic CO_(2)reduction reaction(CO_(2)RR).DFT calculations and experimental studies indicate that the strong carrier effect of PNGC makes PNGC carried Cu-In nanosheets improved the adsorption capacity of CO_(2)gas,reconfigured electronic structure,and reduced free energy of key intermediate formation,thereby the CO_(2)activation and conversion are promoted.
基金National Natural Science Foundation of China(NSFC)(12104358,12104361,12304406,12175168,12404390,92476105,92050103)Shaanxi Fundamental Science Research Project for Mathematics and Physics(22JSQ035,23JSQ014)Postdoctoral Fellowship Program ofChinaPostdoctoral Science Foundation(CPSF)(GZC20232118).
文摘Photonic multi-dimensional storage capabilities and the high storage efficiency of multiplexed quantum storage devices are critical metrics that directly determine the entanglement distribution efficiency of quantum networks.
基金supported by the National Key R&D Program of China(No.2018YFC1802300)Special Project for Basic Scientific Research Operations of Public Welfare Research Institutes at the Central Level(Self-supporting Projects of Institutes)(China)(PM-zx703-202406-192).
文摘The heavy metal pollution in water,largely driven by human activities,has become a significant concern in China.Pyrite has gained attention for treating heavy metal wastewater due to its excellent adsorptive and redox properties,affordability,and environmental compatibility.However,the inherent limitations of natural pyrite,such as its small specific surface area,inadequate active sites,and tendency to agglomerate,hinder its effectiveness in removing heavy metal ions.To address these shortcomings and optimize pyrite’s performance in practical applications,various modification strategies have been developed.In this paper,the oxidation,reduction,and adsorption capabilities of pyrite with respect to different heavy metal ions have been systematically reviewed by the comparison of the underlying mechanisms.We also discussed pyrite modification strategies and their corresponding enhancement mechanisms.Finally,the paper systematically reviews the current application status and future research trends of pyrite and its modified composites in heavy metal wastewater treatment.Basically,this work provides a systematic review on pyrite-based materials for heavy metal removal,from theoretical insights to practical applications and future modification strategies.
基金supported by the National Natural Science Foundation of China(Nos.12104358,12104361,and 12304406)the Shaanxi Fundamental Science Research Project for Mathematics and Physics(Nos.22JSZ004 and 23JSQ014).
文摘The quantum eraser effect exemplifies the distinctive properties of quantum mechanics that challenge classical intuition and reveal the wave-particle duality of light.Whether the photon exhibits particle-like or wave-like behavior depends on whether the path information is discernible.In this paper,we propose a novel quantum eraser scheme that utilizes photonic phase structures as the which-way indicator.This scheme is implemented using a Mach–Zehnder interferometer(MZI),where one arm is configured with orbital angular momentum(OAM)to establish predetermined which-way information.Consequently,at the output ports of the MZI,the photon displays particle-like characteristics when the which-way information is retained.However,the introduction of an additional spiral phase plate(SPP)to eliminate the phase structure from the output photon of the MZI unveils distinct interference patterns.This result enhances our understanding of the quantum erasure effect.
基金National Natural Science Foundation of China(11534008,11574247,11604257,11774286,92050103)Fundamental Research Funds for the Central Universities+1 种基金H2020 Marie Sk?odowska-Curie Actions(721465)Nemzeti Kutatási Fejlesztésiés Innovációs Hivatal(NKFIH)(2017-1.2.1-NKP-2017-00001)。
文摘We propose and demonstrate an experimental implementation for the observation of magnetic fields from spatial features of absorption profiles in a warm atomic vapor.A radially polarized vector beam that traverses atomic vapor will generate an absorption pattern with a petal-like structure by the mediation of a transverse magnetic field(TMF).The spatial absorption pattern rotates when the azimuthal angle of the TMF is changed,while its contrast decreases when the longitudinal component of the magnetic field increases.By analyzing the intensity distribution of the transmitted pattern,we can determine the magnetic field strength.Our work provides a framework for investigating 3 D magnetic field distributions based on atoms.
基金National Natural Science Foundation of China(11534008,11804271,11974345,91736104).
文摘Cylindrical vector beams(CVBs),which possess polarization distribution of rotational symmetry on the transverse plane,can be developed in many optical technologies.Conventional methods to generate CVBs contain redundant interferometers or need to switch among diverse elements,thus being inconvenient in applications containing multiple CVBs.Here we provide a passive polarization-selective device to substitute interferometers and simplify generation setup.It is accomplished by reversing topological charges of orbital angular momentum based on a polarization-selective Gouy phase.In the process,tunable input light is the only condition to generate a CVB with arbitrary topological charges.To cover both azimuthal and radial parameters of CVBs,we express the mapping between scalar Laguerre–Gaussian light on a basic Poincaré sphere and CVB on a high-order Poincaré sphere.The proposed device simplifies the generation of CVBs enormously and thus has potential in integrated devices for both quantum and classic optical experiments.
基金National Natural Science Foundation of China(11534008,91736104)Ministry of Science and Technology of the People's Republic of China(2016YFA0301404)Fundamental Research Funds for the Central Universities.
文摘Orbital angular momentum(OAM)-carrying beams have received extensive attention due to their high-dimensional characteristics in the context of free-space optical communication.However,accurate OAM mode recognition still suffers from reference misalignment of lateral displacement,beam waist size,and initial phase.Here we propose a deep-learning method to exquisitely recognize OAM modes under misalignment by using an alignment-free fractal multipoint interferometer.Our experiments achieve 98.35% recognizing accuracy when strong misalignment is added to hyperfine OAM modes whose Bures distance is 0.01.The maximum lateral displacement we added with respect to the perfectly on-axis beam is about±0.5 beam waist size.This work offers a superstable proposal for OAM mode recognition in the application of free-space optical communication and allows an increase of the communication capacity.
基金This work was financially supported by the National Natural Science Foundation of China(NSFC 81472727,NSFC 81773259 and NSFC 91029718)Science and Technology Commission of Shanghai Municipality(15JC1403100)National laboratory of Oncogene and Cancer-related Genes foundation(90-15-05).
文摘Tumor vasculature constitutes a formidable hurdle for the efficient delivery of cancer nanomedicine into tumors.The leverage of passive pathway through inter-endothelial gaps in tumor blood vessels might account for limited extravasation of nanomedicine into tumor microenvironment(TME).Herein,Annexin A1 antibody-installed mesoporous organosilica nanoplatforms carrying immunotherapeutics of anti-PD-L1 antibody(aPD-L1)and Indoximod are developed to target at caveolar Annexin-A1 protein of luminal endothelial cells and to trigger the active trans-endothelial transcytosis of nanomedicine mediated by caveolae.Such strategy enables rapid nanomedicine extravasation across tumor endothelium and relatively extensive accumulation in tumor interstitium.aPD-L1 and Indoximod release from aPD/IND@MON-aANN in a reduction-responsive manner and synergistically facilitate the intratumoral infiltration of cytotoxic T lymphocytes and reverse the immunosuppressive TME,thus demonstrating substantial anti-tumor efficacy in subcutaneous 4T1 breast tumors and remarkable anti-metastatic capacity to extend the survival of 4T1 tumor metastasis model.Moreover,aPD/IND@MON-aANN nanomedicine also exhibits distinct superiority over the combination therapy of free drugs to potently attenuate the progression of urethane-induced orthotopic lung cancers.Collectively,aPD/IND@MON-aANN nanoplatforms with boosted delivery efficiency via antibody-activated trans-endothelial pathway and enhanced immunotherapeutic efficacy provides perspectives for the development of cancer nanomedicines.
基金Fundamental Research Funds for the Central UniversitiesNational Natural Science Foundation of China(NSFC)(11374008,11374238,11374239,11534008)
文摘Vortex beams with fractional topological charge(FTC) have many special characteristics and novel applications.However, one of the obstacles for their application is the difficulty of precisely determining the FTC of fractional vortex beams. We find that when a vortex beam with an FTC illuminates a dynamic angular double slit(ADS), the far-field interference patterns that include the information of the FTC of the beam at the angular bisector direction of the ADS vary periodically. Based on this property, a simple dynamic ADS device and data fitting method can be used to precisely measure the FTC of a vortex light beam with an error of less than 5%.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.11774286,92050103,12104358,11534008,12033007,and 61875205).
文摘In this article we report on the experimental investigation of light storage for several types of diffractionfree beams(Bessel and Airy beams)and quasi-diffraction-free beams by utilizing electromagnetically induced transparency(EIT)technique in a hot atomic gas cell.The experimental results show that the diffraction-free and quasi-diffraction-free beams have better storage performances when compared with ordinary images possessing similar spatial profiles.Meanwhile,the Bessel beams and the quasidiffraction-free images are able to maintain their spatial profiles with a long storage time while the sidelobes of the Airy beam are gradually depleted with the increment of the storage time.We quantitatively analyze the storage results and give physical explanations behind these phenomena.Furthermore,the self-healing of the retrieved diffraction-free beams is verified,signifying that their characteristics preserve well after storage.
基金supported by the National Natural Science Foundation of China(Grant Nos.11774286,11604258,11534008,11374238,and11574247)the China Postdoctoral Science Foundation(Grant No.2016M592771)
文摘An image undergoes a paraxial diffraction spreading when propagating in free space.The reduction of diffraction is critical for many potential applications[1-3].Recently,it has been recognized that optical diffraction can be greatly suppressed or even eliminated by using atomic coherence effects[4-9].
基金supported by the Shenzhen Science and Technology Program(Grant No.JCYJ20210324101014036).
文摘Excessive mining and utilization fossil fuels has led to drastic environmental consequences,which will contribute to global warming and cause further climate change with severe consequences for the human population.The magnitude of these challenges requires several approaches to develop sustainable alternatives for chemicals and fuels production.In this context,biological processes,mainly microbial fermentation,have gained particular interest.For example,autotrophic gas-fermenting acetogenic bacteria are capable of converting CO,CO_(2) and H_(2) into biomass and multiple metabolites through Wood-Ljungdahl pathway,which can be exploited for large-scale fermentation processes to sustainably produce bulk biochemicals and biofuels(e.g.acetate and ethanol)from syngas.Clostridium autoethanogenum is one representative of these chemoautotrophic bacteria and considered as the model for the gas fermentation.Recently,the development of synthetic biology toolbox for this strain has enabled us to study and genetically improve their metabolic capability in gas fermentation.In this review,we will summarize the recent progress involved in the understanding of physiological mechanism and strain engineering for C.autoethanogenum,and provide our perspectives on the future development about the basic biology and engineering biology of this strain.
基金This work was supported by the National Natural Science Foundation of China(NSFC)(Nos.12104358,12104361,and 92050103)Shaanxi Fundamental Science Research Project for Mathematics and Physics(No.22JSZ004).
文摘We experimentally demonstrate the generation of customized Laguerre–Gaussian(LG)beams whose intensity maxima are localized around any desired curves.The principle is to act with appropriate algebraic functions on the angular spectra of LG beams.We characterize the propagation properties of these beams and compare them with non-diffraction caustic beams possessing the same intensity profiles.The results manifest that the customized-LG beams can maintain their profiles during propagation and suffer less energy loss than the non-diffraction caustic beams,and hence are able to propagate a longer distance.Moreover,the customized-LG beam exhibits self-healing ability when parts of their bodies are blocked.This new structure beam has potential applications in areas such as optical communication,soliton routing and steering,and optical tweezing.
基金financially supported by the Scientific and technological innovation project of the China Academy of Chinese Medical Sciences(CI2021A05032,CI2021B017)the Fundamental Research Funds for the Central Public Welfare Research Institutes(RXRC2022003,XTCX2023001).
文摘Nervonic acid(NA)is an important long-chain monounsaturated fatty acid found in mammalian nervous tissue.It has recently garnered research attention due to its therapeutic potential in treating psychiatric and neurodegenerative disorders.In this study,we investigated the efficacy of NA in treating ischemia/reperfusion and poststroke events in a rat model.Specifically,there was significant reduction in the infarct area,cell death,and neuronal swelling after NA treatment,and the improvement in cerebral blood flow was also observed on day five after middle cerebral artery occlusion.Moreover,NA treatment led to the upregulation of brain-derived neurotrophic factors and myelin basic protein genes.NA displayed improved effects on depressive-like behavior of rats by three validated assays—the sucrose preference test,open-field test,and forced swim test.Regarding the mechanism of action,direct supplementation of NA in the brain was observed.We also observed the indirect effects of NA on the gut microbiota.Notably,the NA group gradually restored the bacterial diversity and the EGb group exhibited no impact based on observed-out analysis.We found an increase in the abundance of Blautia and Sutterella,which participated in phenylalanine metabolism.The metabolomics of plasma and brain samples revealed a decrease in the levels of phenylalanine-based amino acids,which alleviated the inhibitory effects on glutamine metabolism and promoted the recovery and signaling transmission of neurons after stroke.Altogether,our findings suggest that NA can be a viable treatment option for alleviating stroke and its associated poststroke depressive-like behaviors.
基金National Natural Science Foundation of China(NSFC)(11774286,11374238,11534008,11574247)
文摘We investigate the sensitivity of the angular rotation measurement with the method of homodyne detection in SU(2) and SU(1,1) interferometers by employing orbital angular momentum(OAM). By combining a coherent beam with a vacuum beam in an SU(2) interferometer, we get the sensitivity of the angular rotation measurement as 1/(2N^(1/2)l). We can surpass the limit of the angular rotation measurement in an SU(1,1) interferometer by combining a coherent beam with a vacuum beam or a squeezed vacuum beam when the probe beam has OAM. Without injection, the sensitivity can reach 1/(2N^(1/2)l). In addition, by employing another construction of an SU(1,1) interferometer where the pump beam has OAM, with the same injection of an SU(1,1) interferometer, the sensitivity of the angular rotation measurement can be improved by a factor of 2, reaching 1/(4Nl). The results confirm the potential of this technology for precision measurements in angular rotation measurements.
基金supported by the Shaanxi Key Research and Development Project (No. 2019ZDLGY09-10)the Key Scientific and Technological Innovation Team of Shaanxi Province (No. 2018TD-024)+1 种基金the National Basic Research Program of China (973 Program)(No. 2015CB654602)the 111 Project of China(No. B14040)。
文摘A new architecture, naked-eye ghost imaging via photoelectric feedback, is developed that avoids computer algorithm processing. Instead, the proposed scheme uses a photoelectric feedback loop to first realize the correlation(multiplication) process of the traditional ghost imaging system. Then, the vision persistence effect of the naked eye is exploited to implement the integral process and to generate negative images. Two kinds of feedback circuits, the digital circuit and the analog circuit, are presented that can achieve a feedback operation. Based on this design, high-contrast real-time imaging of moving objects is obtained via a special pattern-scanning architecture on a low-speed light-modulation mask.
基金supported by the Fundamental Research Funds for the Central Universitiesthe National Natural Science Foundation of China(Nos.11774286,11374238,11574247,11374008,and 11534008)
文摘We demonstrate the generation of non-classical photon pairs in a warm S-Rb atomic vapor （＇ell with no buffer gas or polarization preserving coatings via spontaneous four-wave mixing. We obtain the photon pairs with a 1/e correlation time of 40 ns and the violation of Cauchy-Sehwartz inequality by a factor of 23 - 3. This provides a convenient and efficient method to generate photon pair sources based on an atomic ensemble.
