A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electro...A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electrons in a metal are resonated with photons.The structural parameters are fine-tuned and the sensing performance of the sensor is studied.The results show that the maximum spectral sensitivity reaches 18 000 nm/RIU in the refractive index range of 1.24—1.32,and the maximum resolution is 5.56×10^(-6) RIU.The novel structure with high sensitivity and low refractive index provides a new perspective for fluid density detection.展开更多
Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves....Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing.展开更多
Plasmonic colors are attracting attention for their subwavelength small size,vibrant hues,and environmental sustainability beyond traditional pigments while suffering from angular and/or polarization dependency due to...Plasmonic colors are attracting attention for their subwavelength small size,vibrant hues,and environmental sustainability beyond traditional pigments while suffering from angular and/or polarization dependency due to distinct excitations of lattice resonances and/or surface plasmon polaritons(SPPs).Here,we demonstrate the sodium metasurface-based plasmonic color palettes with polarization-independent wide-view angle(approximately>〓〓60 deg in experiment and up to〓〓90 deg in theory)and single-particlelevel pixel size(down to∼60 nm)that integrate both pigment-like and structure coloring advantages,fabricated by the templated nanorod-pixelated solidification of wetted liquid metals.Such intriguing performances are mainly attributed to the particle plasmon dominant spectral response by steering the filling profile and thus the interplay between localized surface plasmons and SPPs.Combining low material cost,potentially scalable manufacturing process,and pronounced optical performance,the proposed sodium-based metasurfaces will provide a promising route for advanced color information technology.展开更多
Meta-devices have significantly revitalized the study of nonlinear optical phenomena.At the nanoscale,the detrimental effects of phase mismatching between fundamental and harmonic waves can be substantially reduced.Th...Meta-devices have significantly revitalized the study of nonlinear optical phenomena.At the nanoscale,the detrimental effects of phase mismatching between fundamental and harmonic waves can be substantially reduced.This review analyzes the theoretical frameworks of how plasmonic and dielectric materials induce nonlinear optical properties.Plasmonic and dielectric nonlinear meta-devices that can excite strong resonant modes for efficiency enhancement are explored.We outline different strategies designed to shape the radiation pattern in order to increase the collection capability of nonlinear signals emitted from meta-devices.In addition,we discuss how nonlinear phase manipulation in meta-devices can integrate the benefits of efficiency enhancement and radiation shaping,not only boosting the energy density of the nonlinear signal but also facilitating a wide range of applications.Finally,potential research directions within this field are discussed.展开更多
Structural engineering enhances plasmonic stability and amplifies localized electric fields,yet the limited intrinsic activity of plasmonic materials necessitates integrating catalytic active sites.Herein,we design a ...Structural engineering enhances plasmonic stability and amplifies localized electric fields,yet the limited intrinsic activity of plasmonic materials necessitates integrating catalytic active sites.Herein,we design a yolk@shell nanoreactor featuring dual-plasmonic Au@CuS core-shell structures encapsulated by sulfur vacancy-rich ZnIn2S4(Sv-ZIS).The electromagnetic“hotspots”from Au and CuS near-field coupling concentrate incident light to boost hot-carrier generation and migration while sulfur vacancies in Sv-ZIS promote hydrogen evolution.This dual mechanism synergistically achieves 86.3 mmol g^(-1)h-1of H2production(65.6%quantum efficiency at 420 nm),maintaining 48.3 mmol g^(-1)h-1at 6℃.Density functional theory(DFT)simulations demonstrate that sulfur vacancies not only reduce the H*adsorption energy barrier from 0.87 to 0.11 eV but also amplify the interfacial electric field strength by 9%.Vacancy-redirected fields favor proton reduction pathways,accelerating charge transfer kinetics.Comparative studies confirm the universal superiority of dual-plasmonic architecture,while Sv-ZIS shells exhibit optimized activity through defect-mediated electronic interactions.This work provides a blueprint for bridging plasmonic field enhancement and defect engineering in multi-component photocatalysts.展开更多
Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic v...Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic vortices(PVs)on chips,and active manipulation as well as multiplexing in more channels have become a pressing demand.In this work,we demonstrate a terahertz(THz)cascaded metadevice composed of a helical plasmonic metasurface,a liquid crystal(LC)layer,and a helical dielectric metasurface.By spin-orbital angular momentum coupling and photon state superposition,PVs and FVs are generated with mode purity of over 85%on average.Due to the inversion asymmetric design of the helical metasurfaces,the parity symmetry breaking of OAM is realized(the topological charge numbers no longer occur in positive and negative pairs,but all are positive),generating 6 independent channels associated with the decoupled spin states and the near-/far-field positions.Moreover,by the LC integration,dynamic mode switching and energy distribution can be realized,finally obtaining up to 12 modes with a modulation ratio of above 70%.This active tuning and multi-channel multiplexing metadevice establishes a bridge connection between the PVs and FVs,exhibiting promising applications in THz communication,intelligent perception,and information processing.展开更多
Tamm plasmon polaritons(TPPs)are localized photonic states at the interface between a metal layer and one-dimensional(1D)photonic crystal substrate.Unlike surface plasmon polaritons(SPPs),TPPs can be excited by both t...Tamm plasmon polaritons(TPPs)are localized photonic states at the interface between a metal layer and one-dimensional(1D)photonic crystal substrate.Unlike surface plasmon polaritons(SPPs),TPPs can be excited by both transverse magnetic and electric waves without requiring additional coupling optics.TPPs offer robust color filtering,making them ideal for applications such as complementary metal oxide semiconductor(CMOS)image detectors.However,obtaining a large-area,reversible,and reconfigurable filter remains challenging.This study demonstrates a dynamically reconfigurable reflective color filter by integrating an ultrathin antimony trisulfide(Sb_(2)S_(3))layer with Tamm plasmonic photonic crystals.Reconfigurable tuning was achieved by inducing Sb_(2)S_(3) crystallization and reamorphization via thermal and optical activation,respectively.The material exhibited good stability after multiple switching cycles.The reflectance spectrum can be tuned across the visible range,with a shift of approximately 50 nm by switching Sb_(2)S_(3) between its amorphous and crystalline phases.This phase transition is nonvolatile and substantially minimizes the energy consumption,enhancing efficiency for practical applications.Tamm plasmonic photonic crystals are low-cost and large-scale production,offering a platform for compact color display systems and customizable photonic crystal filters for realistic system integration.展开更多
Confronting the escalating global challenge of counterfeit products,developing advanced anticounterfeiting materials and structures with physical unclonable functions(PUFs)has become imperative.All-optical PUFs,distin...Confronting the escalating global challenge of counterfeit products,developing advanced anticounterfeiting materials and structures with physical unclonable functions(PUFs)has become imperative.All-optical PUFs,distinguished by their high output complexity and expansive response space,offer a promising alternative to conventional electronic counterparts.For practical authentications,the expansion of optical PUF keys usually involves intricate spatial or spectral shaping of excitation light using bulky external apparatus,which largely hinders the applications of optical PUFs.Here,we report a plasmonic PUF system based on heterogeneous nanostructures.The template-assisted shadow deposition technique was employed to adjust the morphological diversity of densely packed metal nanoparticles in individual PUFs.Transmission images were processed via a hash algorithm,and the generated PUF keys with a scalable capacity from 2875 to 243401 exhibit excellent uniqueness,randomness,and reproducibility.Furthermore,the wavelength and the polarization state of the excitation light are harnessed as two distinct expanding strategies,offering the potential for multiscenario applications via a single PUF.Overall,our reported plasmonic PUFs operated with the multidimensional expanding strategy are envisaged to serve as easy-to-integrate,easy-to-use systems and promise efficacy across a broad spectrum of applications,from anticounterfeiting to data encryption and authentication.展开更多
The increasing importance of high-purity isopropyl alcohol(IPA)in semiconductor processing technology has led to a higher demand for technologies capable of detecting impurities in IPA.Although accurate and various im...The increasing importance of high-purity isopropyl alcohol(IPA)in semiconductor processing technology has led to a higher demand for technologies capable of detecting impurities in IPA.Although accurate and various impurity detection technologies have been developed,most of them have limitations in real-time and repeatable detection of impurities.Herein,for the first time,surface plasmon resonance(SPR)sensor was developed utilizing graphene transferred Au film(Au/graphene)to detect sub-ppm levels of 2,4-dinitrophenol(2,4-DNP)dissolved in IPA and this sensor demonstrates the ability to detect 2,4-DNP in real-time with great reversibility.The adsorption of 2,4-DNP to graphene is found to be stronger than that for Au film because of noncovalent graphene p–p stacking interaction,and the effect of graphene is demonstrated through density function theory(DFT)calculations and enhancement in sensing performance of Au/graphene sensor.Additionally,the presence of noncovalent p–p stacking interaction between 2,4-DNP and graphene has been demonstrated by confirming the p-doping effect of graphene-based solution field-effect transistor measurements and consecutive Raman spectra analysis.This study offers experimental and theoretical insights into the adsorption kinetics of 2,4-DNP dissolved in IPA and provides promising perspectives for real-time sensing technology utilizing label-free graphene to detect impurities in high-purity cleaning agents.展开更多
The construction of a well-defined and efficient Z-scheme heterostructure with enhanced photogenerated charge carriers and their rapid transfer is vital for realizing efficient photocatalytic hydrogen production,to ac...The construction of a well-defined and efficient Z-scheme heterostructure with enhanced photogenerated charge carriers and their rapid transfer is vital for realizing efficient photocatalytic hydrogen production,to achieve carbon neutrality.Herein,we study the H_(2)evolution reaction by rationally constructing a hybrid Au-anchored UiO-66-NH_(2)with localized surface plasmon resonance(LSPR)properties,embedded with ZnIn_(2)S_(4)/MoS_(2)nanosheets.Interestingly,the synergistic effect of excellent heterojunction,tunes additional catalytic active sites,provides effective separation of photogenerated charges at the junction interface and establishes a dedicated microenvironment for the boosted electron transfer.Notably,the optimized hybrid photocatalyst(Au6@U6N)15/ZIS/MS5 exhibits highly efficient H_(2)generation of 58.2 mmol g^(-1)h^(-1),which is almost 16 and 1.5 folds of the pristine ZIS and MS/U6N/ZIS,correspondingly.It has an apparent quantum efficiency of 19.6%at a wavelength of 420 nm,surpassing several reported MOF-based ZnIn_(2)S_(4)photocatalytic H_(2)evolution activities.Significantly,this research provides insights into the design of interface-engineered plasmonic MOF with layered encapsulated heterostructures that elucidate the role of plasmonic LSPR effect and efficiently regulate the charge transfer with enhanced microchannels,hence boosting the visible-light-driven photocatalytic activity for realizing efficient green energy conversion.展开更多
Negative friction refers to a frictional force that acts in the same direction as the motion of an object, which has been predicted in terahertz(THz) gain systems [Phys. Rev. B 108 045406(2023)]. In this work, we inve...Negative friction refers to a frictional force that acts in the same direction as the motion of an object, which has been predicted in terahertz(THz) gain systems [Phys. Rev. B 108 045406(2023)]. In this work, we investigate the enhancement of the negative friction experienced by nanospheres placed near a graphene substrate. We find that the magnitude of negative friction is related to the resonant coupling between the surface plasmon polaritons(SPPs) of the graphene and localized surface phonon polaritons(LSPh P) of nanospheres. We exam nanospheres consisted of several different materials, including SiO_(2), Si C, Zn Se, Na Cl, ln Sb. Our results suggest that the LSPh P of Na Cl nanospheres match effectively with the amplified SPPs of graphene sheets. The negative friction for Na Cl nanospheres can be enhanced about one-to-two orders of magnitude compared to that of silica(SiO_(2)) nanospheres. At the resonant peak of negative friction, the required quasi-Fermi energy of graphene is lower for Na Cl nanospheres. Our finds hold great prospects for the mechanical manipulations of nanoscale particles.展开更多
The photothermal properties of dielectric materials at the nanoscale have garnered significant attention,especially in fields such as optical heating,photothermal therapy,and solar utilization.However,although dielect...The photothermal properties of dielectric materials at the nanoscale have garnered significant attention,especially in fields such as optical heating,photothermal therapy,and solar utilization.However,although dielectric materials can concentrate and manipulate light at the nanoscale,they cannot provide sufficient photothermal efficiency in a direct absorption solar collector.Combining plasmonic metal nanoparticles with dielectric nanostructures enables the fabrication of hybrid nanomaterials with excellent photothermal performance.This study presents a novel approach involving uniformly adhering plasmonic gold nanoparticles onto dielectric silicon nanoparticles to enhance the absorption peak,leading to a substantial enhancement of photothermal conversion efficiency.The results demonstrate that the absorption peak of silicon-gold hybrid nanoparticles exceeds that of pure silicon nanoparticles,achieving a 38%increase in photothermal conversion efficiency within a 10 ppm aqueous solution under a 20 mm optical path.The coupling of localized surface plasmon resonance and quadrupole resonance effects enhances the electric field,causing a temperature rise in both the hybrid nanoparticles and the surrounding aqueous solution.Nanostructural modulation studies reveal that the photothermal efficiency of silicon-gold hybrid nanoparticles is positively correlated with gold nanoparticle size but negatively correlated with silicon nanoparticle size.Combining multiple plasmonic nanoparticles with dielectric materials can effectively enhance photothermal performance and hold great application potential in direct absorption solar collectors and solar thermal utilization.展开更多
Accurate and real-time detection of hydrogen(H_(2))is essential for ensuring energy security.Fiber-optic H_(2) sensors are gaining attention for their integration and remote sensing capabilities.However,they face chal...Accurate and real-time detection of hydrogen(H_(2))is essential for ensuring energy security.Fiber-optic H_(2) sensors are gaining attention for their integration and remote sensing capabilities.However,they face challenges,including complex fabrication processes and limited response times.Here,we propose a fiber-optic H_(2) sensing tip based on Tamm plasmon polariton(TPP)resonance,consisting of a multilayer metal/dielectric Bragg reflector deposited directly on the fiber end facet,simplifying the fabrication process.The fiber-optic TPP(FOTPP)tip exhibits both TPP and multiple Fabry-Perot(FP)resonances simultaneously,with the TPP employed for highly sensitive H_(2) detection.Compared to FP resonance,TPP exhibits more than twice the sensitivity under the same structural dimension without cavity geometry deformation.The excellent performance is attributed to alterations in phase-matching conditions,driven by changes in penetration depth of TPP.Furthermore,the FP mode is utilized to achieve an efficient photothermal effect to catalyze the reaction between H_(2) and the FOTPP structure.Consequently,the response and recovery speeds of the FOTPP tip under resonance-enhanced photothermal assistance are improved by 6.5 and 2.1 times,respectively.Our work offers a novel strategy for developing TPP-integrated fiber-optic tips,refines the theoretical framework of photothermal-assisted detection systems,and provides clear experimental evidence.展开更多
Metal micro-nano grating has received much attention due to its ability to provide high-efficiency light absorption.However,the current research scales of these metal gratings are focused on subwavelengths,and little ...Metal micro-nano grating has received much attention due to its ability to provide high-efficiency light absorption.However,the current research scales of these metal gratings are focused on subwavelengths,and little attention has been paid to the absorption properties of metal gratings at other scales.We investigate the absorption properties of metal gratings based on surface plasmon resonance(SPR)across the scales from superwavelength to subwavelength.Under grazing incidence,we observe continuous strong absorption phenomena from superwavelength to subwavelength Al triangle-groove gratings(TGGs).Perfect absorption is realized at the subwavelength scale,whereas the maximum absorption at all other scales exceeds 74%.The electric field distribution gives the mechanism of the strong absorption phenomenon attributed to SPR on the surface of Al TGGs at different scales.In particular,subwavelength Al TGGs have perfectly symmetric absorption properties for different blaze angles,and the symmetry is gradually broken as the grating period’s scale increases.Furthermore,taking Al gratings with varying groove shapes for example,we extend the equivalence rule of grating grooves to subwavelength from near-wavelength and explain the symmetric absorption properties in Al TGGs.We unify the research of metal grating absorbers outside the subwavelength scale to a certain extent,and these findings also open new perspectives for the design of metal gratings in the future.展开更多
There is limited amount of research on surface plasmon resonance(SPR)sensors with self-referencing capabilities which are based on dielectric gratings.In the short-wavelength range,a metal grating sensor is capable of...There is limited amount of research on surface plasmon resonance(SPR)sensors with self-referencing capabilities which are based on dielectric gratings.In the short-wavelength range,a metal grating sensor is capable of simultaneously measuring liquid refractive index under proposed temperature.A fabricated gold grating is placed on one side of a thin gold film for refractive index measurement,while the other with polydimethylsiloxane(PDMS)is deposited on the other side for temperature measurement.We use finite element analysis to research its sensing characteristics.Due to the high refractive index sensitivity of SPR sensors and thermo-optic coefficient of PDMS,we discovered the maximum spectral sensitivity of the sensor is 564 nm/RIU and-50 pm/℃when the liquid refractive index ranges from 1.30 to 1.40 with temperature ranging from 0℃ to 100℃.Numerical results indicate that there may not be mutual interference between two channels for measuring refractive index and temperature,which reduces the complexity of sensor measurements.展开更多
Piezoelectric effect,plasma effect and semiconductor heterostructure are important strategies for enhanced photocatalytic performance.Herein,we developed a novel heterostructure piezoelectric photocatalyst,Ag/Ag_(2)S/...Piezoelectric effect,plasma effect and semiconductor heterostructure are important strategies for enhanced photocatalytic performance.Herein,we developed a novel heterostructure piezoelectric photocatalyst,Ag/Ag_(2)S/BiFeO_(3)(AAS/BFO),for photocatalytic degradation of ciprofloxacin from water.Experimental results verified the enhancement of combining heterostructure piezoelectric polarization effect,which promotes efficient migration and separation of photogenerated carriers due to the localized surface plasmon resonance effect of Ag nanoparticles.Additionally,the introduction of Ag_(2)S constructs a new heterostructure,that enhances the electron transport rate and improves the separation efficiency on electron-hole pairs.Under ultrasonic stimulation and visible light irradiation,the degradation efficiencies of 15%-AAS/BFO towards ciprofloxacin,methyl orange and methylene blue are significantly enhanced compared to pure BFO fibers.The demonstrated AAS/BFO material based on the synergistic piezoelectric effect and plasmon heterostructure shows potential in efficient organic pollutants water treatment and transforming mechanical energy into chemical energy.展开更多
A triple-band miniaturized end-fire antenna based on the odd modes of spoof surface plasmonic polariton(SSPP)waveguide resonator is proposed in this paper.To meet the ever increasing demand for more communication chan...A triple-band miniaturized end-fire antenna based on the odd modes of spoof surface plasmonic polariton(SSPP)waveguide resonator is proposed in this paper.To meet the ever increasing demand for more communication channels and less antenna sizes,multi-band antennas are currently under intensive investigation.By a novel feeding method,three odd modes are excited on an SSPP waveguide resonator,which performs as an end-fire antenna operating at three bands,7.15-7.26 GHz,11.6-12.2 GHz and 13.5-13.64 GHz.It exhibits reasonably high and stable maximum gains of 5.26 dBi,7.97 dBi and 10.1 dBi and maximum efficiencies of 64%,92%and 98%at the three bands,respectively.Moreover,in the second band,the main beam angle shows a frequency dependence with a total scanning angle of 19°.The miniaturized triple-band antenna has a great potential in wireless communication systems,satellite communication and radar systems.展开更多
A Luttinger liquid is a theoretical model describing interacting electrons in one-dimensional(1D)conductors.While individual 1D conductors have shown interesting Luttinger-liquid behaviors such as spin-charge separati...A Luttinger liquid is a theoretical model describing interacting electrons in one-dimensional(1D)conductors.While individual 1D conductors have shown interesting Luttinger-liquid behaviors such as spin-charge separation and power-law spectral density,the more interesting phenomena predicted in coupled Luttinger liquids of neighboring 1D conductors have been rarely observed due to the difficulty in creating such structures.Recently,we have successfully grown close-packed carbon nanotube(CNT)arrays with uniform chirality,providing an ideal material system for studying the coupled Luttinger liquids.Here,we report on the observation of tunable hyperbolic plasmons in the coupled Luttinger liquids of CNT arrays using scanning near-field optical microscopy.These hyperbolic plasmons,resulting from the conductivity anisotropy in the CNT array,exhibit strong spatial confinement,in situ tunability,and a wide spectral range.Despite their hyperbolic wavefronts,the plasmon propagation in the axial direction still adheres to the Luttinger-liquid theory.Our work not only demonstrates a fascinating phenomenon in coupled Luttinger liquids for fundamental physics exploration,but also provides a highly confined and in situ tunable hyperbolic plasmon in close-packed CNT arrays for future nanophotonic devices and circuits.展开更多
Devising S-scheme heterostructure is considered as a cutting-edge strategy for advanced photocatalysts with effectively segregated photo-carriers and prominent redox potential for emerging organic pollutants control.H...Devising S-scheme heterostructure is considered as a cutting-edge strategy for advanced photocatalysts with effectively segregated photo-carriers and prominent redox potential for emerging organic pollutants control.Herein,an S-scheme Ag_(2)CO_(3)/C_(3)N_(5) heterojunction photocatalyst was developed via a simple in situ chemical deposition procedure,and further photoreduction operation made metallic Ag(size:3.5–12.5 nm)being in situ formed on Ag_(2)CO_(3)/C_(3)N_(5) for a plasmonic S-scheme Ag/Ag_(2)CO_(3)/C_(3)N_(5) heterojunction photocatalyst.Consequently,Ag/Ag_(2)CO_(3)/C_(3)N_(5) manifests pronouncedly upgraded photocatalytic performance toward oxytetracycline degradation with a superior photoreaction rate constant of 0.0475 min‒1,which is 13.2,3.9 and 2.2 folds that of C_(3)N_(5),Ag_(2)CO_(3),and Ag_(2)CO_(3)/C_(3)N_(5),respectively.As evidenced by comprehensive characterizations and density functional theory calculations,the localized surface plasmon resonance effect of metallic Ag and the unique S-scheme charge transfer mechanism in 0D/0D/2D Ag/Ag_(2)CO_(3)/C_(3)N_(5) collaboratively strengthen the visible-light absorption,and facilitate the effective separation of powerful charge carriers,thereby significantly promoting the generation of reactive species like·OH^(-),h^(+)and·O_(2)^(-)for efficient oxytetracycline destruction.Moreover,four consecutive cycles demonstrate the reusability of Ag/Ag_(2)CO_(3)/C_(3)N_(5).Furthermore,the authentic water purification tests affirm its practical application potential.This work not only provides a candidate strategy for advancing S-scheme heterojunction photocatalysts but also makes a certain contribution to water decontamination.展开更多
Nano-optics is an emergent research field in physics that appeared in the 1980s,which deals with light–matter optical interactions at the nanometer scale.In early studies of nano-optics,the main concern focus is to o...Nano-optics is an emergent research field in physics that appeared in the 1980s,which deals with light–matter optical interactions at the nanometer scale.In early studies of nano-optics,the main concern focus is to obtain higher optical resolution over the diffraction limit.The researches of near-field imaging and spectroscopy based on scanning near-field optical microscopy(SNOM)are developed.The exploration of improving SNOM probe for near-field detection leads to the emergence of surface plasmons.In the sense of resolution and wider application,there has been a significant transition from seeking higher resolution microscopy to plasmonic near-field modulations in the nano-optics community during the nano-optic development.Nowadays,studies of nano-optics prefer the investigation of plasmonics in different material systems.In this article,the history of the development of near-field optics is briefly reviewed.The difficulties of conventional SNOM to achieve higher resolution are discussed.As an alternative solution,surface plasmons have shown the advantages of higher resolution,wider application,and flexible nano-optical modulation for new devices.The typical studies in different periods are introduced and characteristics of nano-optics in each stage are analyzed.In this way,the evolution progress from near-field optics to plasmonics of nano-optics research is presented.The future development of nano-optics is discussed then.展开更多
基金supported by the Natural Science Foundation of Tianjin City (No.19JCYBJC17000)the National Natural Science Foundation of China (No.11905159)。
文摘A D-type photonic crystal fiber(PCF) sensor based on surface plasmon resonance(SPR) principle is designed.In order to excite the SPR effect,a gold film is plated on the open-loop channel of the sensor,the free electrons in a metal are resonated with photons.The structural parameters are fine-tuned and the sensing performance of the sensor is studied.The results show that the maximum spectral sensitivity reaches 18 000 nm/RIU in the refractive index range of 1.24—1.32,and the maximum resolution is 5.56×10^(-6) RIU.The novel structure with high sensitivity and low refractive index provides a new perspective for fluid density detection.
基金financial supports from National Natural Science Foundation of China(No.61905051)Natural Science Foundation of Heilongjiang Province(No.LH2020F027).
文摘Periodic metal nanoarrays serving as cavities can support directional-tunable amplified spontaneous emission that goes beyond the diffraction limit due to the hybrid states of surface plasmons and Bloch surface waves.Most of these modes'interactions remain within the weak coupling regime,yet strong coupling is also anticipated to occur.In this work,we present an intriguing case of amplified spontaneous emission(ASE),amplified by the splitting upper polariton mode within a strong coupling system,stemming from a square lattice of plasmonic cone lattices(PCLs).The PCLs are fabricated using an anodized aluminum oxide membrane(AAO),which facilitates strong coupling between surface plasmons and Bloch surface wave modes,with the maximum Rabi splitting observed at 0.258 eV for the sample with an aspect ratio of 0.33.A 13.5-fold increase in amplified spontaneous emission is recorded when the emission from Nile Red coincides with this flat energy branch of upper polariton,which exhibits a high photon density of states.Reduced group velocity can prolong photon lifetime and boost the probability of light-matter interaction.The observed ASE phenomenon in this strong coupling plasmonic system widens the scope for applications in nanolasing and polariton lasing.
基金supported by the National Key Research and Development Program of China(Grant Nos.2021YFA1400700 and 2022YFA1404300)the National Natural Science Foundation of China(Grant Nos.12022403 and 62375123)the Natural Science Foundation of Jiangsu Province(Grant No.BK20243009).
文摘Plasmonic colors are attracting attention for their subwavelength small size,vibrant hues,and environmental sustainability beyond traditional pigments while suffering from angular and/or polarization dependency due to distinct excitations of lattice resonances and/or surface plasmon polaritons(SPPs).Here,we demonstrate the sodium metasurface-based plasmonic color palettes with polarization-independent wide-view angle(approximately>〓〓60 deg in experiment and up to〓〓90 deg in theory)and single-particlelevel pixel size(down to∼60 nm)that integrate both pigment-like and structure coloring advantages,fabricated by the templated nanorod-pixelated solidification of wetted liquid metals.Such intriguing performances are mainly attributed to the particle plasmon dominant spectral response by steering the filling profile and thus the interplay between localized surface plasmons and SPPs.Combining low material cost,potentially scalable manufacturing process,and pronounced optical performance,the proposed sodium-based metasurfaces will provide a promising route for advanced color information technology.
基金supported by the University Grants Committee/Research Grants Council of the Hong Kong Special Administrative Region,China(AoE/P-502/20,C1015-21E,C5031-22G,CityU15303521,CityU11305223,CityU11310522,CityU11300123,and G-CityU 101/22)the City University of Hong Kong(9380131 and 7005867)the National Natural Science Foundation of China(62375232).
文摘Meta-devices have significantly revitalized the study of nonlinear optical phenomena.At the nanoscale,the detrimental effects of phase mismatching between fundamental and harmonic waves can be substantially reduced.This review analyzes the theoretical frameworks of how plasmonic and dielectric materials induce nonlinear optical properties.Plasmonic and dielectric nonlinear meta-devices that can excite strong resonant modes for efficiency enhancement are explored.We outline different strategies designed to shape the radiation pattern in order to increase the collection capability of nonlinear signals emitted from meta-devices.In addition,we discuss how nonlinear phase manipulation in meta-devices can integrate the benefits of efficiency enhancement and radiation shaping,not only boosting the energy density of the nonlinear signal but also facilitating a wide range of applications.Finally,potential research directions within this field are discussed.
基金supported by the National Natural Science Foundation of China(22162007)the Science and Technology Supporting Project of Guizhou Province([2021]480)+1 种基金the Science and Technology Supporting Project of Guizhou Province([2023)379)the Project from Guizhou Institute of Innovation and development of dual-carbon and new energy technologies(DCRE-2023-05)。
文摘Structural engineering enhances plasmonic stability and amplifies localized electric fields,yet the limited intrinsic activity of plasmonic materials necessitates integrating catalytic active sites.Herein,we design a yolk@shell nanoreactor featuring dual-plasmonic Au@CuS core-shell structures encapsulated by sulfur vacancy-rich ZnIn2S4(Sv-ZIS).The electromagnetic“hotspots”from Au and CuS near-field coupling concentrate incident light to boost hot-carrier generation and migration while sulfur vacancies in Sv-ZIS promote hydrogen evolution.This dual mechanism synergistically achieves 86.3 mmol g^(-1)h-1of H2production(65.6%quantum efficiency at 420 nm),maintaining 48.3 mmol g^(-1)h-1at 6℃.Density functional theory(DFT)simulations demonstrate that sulfur vacancies not only reduce the H*adsorption energy barrier from 0.87 to 0.11 eV but also amplify the interfacial electric field strength by 9%.Vacancy-redirected fields favor proton reduction pathways,accelerating charge transfer kinetics.Comparative studies confirm the universal superiority of dual-plasmonic architecture,while Sv-ZIS shells exhibit optimized activity through defect-mediated electronic interactions.This work provides a blueprint for bridging plasmonic field enhancement and defect engineering in multi-component photocatalysts.
基金supported by the National Natural Science Foundation of China(62335012,62371258,624B2075,62205160,62435010)Young Scientific and Technological Talents in Tianjin(QN20230227)Fundamental Research Funds for the Central Universities,Nankai University(63231159).
文摘Vortex beams carrying orbital angular momentum(OAM)are of great significance for high-capacity communication and super-resolution imaging.However,there is a huge gap between the free-space vortices(FVs)and plasmonic vortices(PVs)on chips,and active manipulation as well as multiplexing in more channels have become a pressing demand.In this work,we demonstrate a terahertz(THz)cascaded metadevice composed of a helical plasmonic metasurface,a liquid crystal(LC)layer,and a helical dielectric metasurface.By spin-orbital angular momentum coupling and photon state superposition,PVs and FVs are generated with mode purity of over 85%on average.Due to the inversion asymmetric design of the helical metasurfaces,the parity symmetry breaking of OAM is realized(the topological charge numbers no longer occur in positive and negative pairs,but all are positive),generating 6 independent channels associated with the decoupled spin states and the near-/far-field positions.Moreover,by the LC integration,dynamic mode switching and energy distribution can be realized,finally obtaining up to 12 modes with a modulation ratio of above 70%.This active tuning and multi-channel multiplexing metadevice establishes a bridge connection between the PVs and FVs,exhibiting promising applications in THz communication,intelligent perception,and information processing.
文摘Tamm plasmon polaritons(TPPs)are localized photonic states at the interface between a metal layer and one-dimensional(1D)photonic crystal substrate.Unlike surface plasmon polaritons(SPPs),TPPs can be excited by both transverse magnetic and electric waves without requiring additional coupling optics.TPPs offer robust color filtering,making them ideal for applications such as complementary metal oxide semiconductor(CMOS)image detectors.However,obtaining a large-area,reversible,and reconfigurable filter remains challenging.This study demonstrates a dynamically reconfigurable reflective color filter by integrating an ultrathin antimony trisulfide(Sb_(2)S_(3))layer with Tamm plasmonic photonic crystals.Reconfigurable tuning was achieved by inducing Sb_(2)S_(3) crystallization and reamorphization via thermal and optical activation,respectively.The material exhibited good stability after multiple switching cycles.The reflectance spectrum can be tuned across the visible range,with a shift of approximately 50 nm by switching Sb_(2)S_(3) between its amorphous and crystalline phases.This phase transition is nonvolatile and substantially minimizes the energy consumption,enhancing efficiency for practical applications.Tamm plasmonic photonic crystals are low-cost and large-scale production,offering a platform for compact color display systems and customizable photonic crystal filters for realistic system integration.
基金supported by the National Natural Science Foundation of China(Grant Nos.62422503,62105080,22004016,and U22A2093)the Guangdong Basic and Applied Basic Research Foundation Regional Joint Fund(Grant Nos.2023A1515011944,2020B1515130006,and 2021B515120056)+1 种基金the Talent Recruitment Project of Guangdong(Grant No.2021QN02X179)the Science and Technology Innovation Commission of Shenzhen(Grant Nos.JCYJ20220531095604009 and RCYX20221008092907027).
文摘Confronting the escalating global challenge of counterfeit products,developing advanced anticounterfeiting materials and structures with physical unclonable functions(PUFs)has become imperative.All-optical PUFs,distinguished by their high output complexity and expansive response space,offer a promising alternative to conventional electronic counterparts.For practical authentications,the expansion of optical PUF keys usually involves intricate spatial or spectral shaping of excitation light using bulky external apparatus,which largely hinders the applications of optical PUFs.Here,we report a plasmonic PUF system based on heterogeneous nanostructures.The template-assisted shadow deposition technique was employed to adjust the morphological diversity of densely packed metal nanoparticles in individual PUFs.Transmission images were processed via a hash algorithm,and the generated PUF keys with a scalable capacity from 2875 to 243401 exhibit excellent uniqueness,randomness,and reproducibility.Furthermore,the wavelength and the polarization state of the excitation light are harnessed as two distinct expanding strategies,offering the potential for multiscenario applications via a single PUF.Overall,our reported plasmonic PUFs operated with the multidimensional expanding strategy are envisaged to serve as easy-to-integrate,easy-to-use systems and promise efficacy across a broad spectrum of applications,from anticounterfeiting to data encryption and authentication.
基金financially supported by National R&D Program(RS-2024-00405016)Nano Material Technology Development Program(2022M3HA1A01011993)financially supported by Samsung Electronics Co.,Ltd.
文摘The increasing importance of high-purity isopropyl alcohol(IPA)in semiconductor processing technology has led to a higher demand for technologies capable of detecting impurities in IPA.Although accurate and various impurity detection technologies have been developed,most of them have limitations in real-time and repeatable detection of impurities.Herein,for the first time,surface plasmon resonance(SPR)sensor was developed utilizing graphene transferred Au film(Au/graphene)to detect sub-ppm levels of 2,4-dinitrophenol(2,4-DNP)dissolved in IPA and this sensor demonstrates the ability to detect 2,4-DNP in real-time with great reversibility.The adsorption of 2,4-DNP to graphene is found to be stronger than that for Au film because of noncovalent graphene p–p stacking interaction,and the effect of graphene is demonstrated through density function theory(DFT)calculations and enhancement in sensing performance of Au/graphene sensor.Additionally,the presence of noncovalent p–p stacking interaction between 2,4-DNP and graphene has been demonstrated by confirming the p-doping effect of graphene-based solution field-effect transistor measurements and consecutive Raman spectra analysis.This study offers experimental and theoretical insights into the adsorption kinetics of 2,4-DNP dissolved in IPA and provides promising perspectives for real-time sensing technology utilizing label-free graphene to detect impurities in high-purity cleaning agents.
基金supported by the National Natural Science Foundationof China (No.52276216)the International Partnership Program ofChinese Academy of Sciences (No.123GJHZ2022055MI)+1 种基金the AnhuiProvincial Natural Science Foundation (No.2108085UD03)the Fundamental Research Funds for the Central Universities
文摘The construction of a well-defined and efficient Z-scheme heterostructure with enhanced photogenerated charge carriers and their rapid transfer is vital for realizing efficient photocatalytic hydrogen production,to achieve carbon neutrality.Herein,we study the H_(2)evolution reaction by rationally constructing a hybrid Au-anchored UiO-66-NH_(2)with localized surface plasmon resonance(LSPR)properties,embedded with ZnIn_(2)S_(4)/MoS_(2)nanosheets.Interestingly,the synergistic effect of excellent heterojunction,tunes additional catalytic active sites,provides effective separation of photogenerated charges at the junction interface and establishes a dedicated microenvironment for the boosted electron transfer.Notably,the optimized hybrid photocatalyst(Au6@U6N)15/ZIS/MS5 exhibits highly efficient H_(2)generation of 58.2 mmol g^(-1)h^(-1),which is almost 16 and 1.5 folds of the pristine ZIS and MS/U6N/ZIS,correspondingly.It has an apparent quantum efficiency of 19.6%at a wavelength of 420 nm,surpassing several reported MOF-based ZnIn_(2)S_(4)photocatalytic H_(2)evolution activities.Significantly,this research provides insights into the design of interface-engineered plasmonic MOF with layered encapsulated heterostructures that elucidate the role of plasmonic LSPR effect and efficiently regulate the charge transfer with enhanced microchannels,hence boosting the visible-light-driven photocatalytic activity for realizing efficient green energy conversion.
基金Project supported by the National Natural Science Foundation of China (Grant No. 11804288)the Key Scientific Research Project of Higher Education Institutions in Henan Province, China (Grant No. 20231205164502999)。
文摘Negative friction refers to a frictional force that acts in the same direction as the motion of an object, which has been predicted in terahertz(THz) gain systems [Phys. Rev. B 108 045406(2023)]. In this work, we investigate the enhancement of the negative friction experienced by nanospheres placed near a graphene substrate. We find that the magnitude of negative friction is related to the resonant coupling between the surface plasmon polaritons(SPPs) of the graphene and localized surface phonon polaritons(LSPh P) of nanospheres. We exam nanospheres consisted of several different materials, including SiO_(2), Si C, Zn Se, Na Cl, ln Sb. Our results suggest that the LSPh P of Na Cl nanospheres match effectively with the amplified SPPs of graphene sheets. The negative friction for Na Cl nanospheres can be enhanced about one-to-two orders of magnitude compared to that of silica(SiO_(2)) nanospheres. At the resonant peak of negative friction, the required quasi-Fermi energy of graphene is lower for Na Cl nanospheres. Our finds hold great prospects for the mechanical manipulations of nanoscale particles.
基金supported by the National Natural Science Foundation of China(Grant No.52106099)the Taishan Scholars Program of Shandong.
文摘The photothermal properties of dielectric materials at the nanoscale have garnered significant attention,especially in fields such as optical heating,photothermal therapy,and solar utilization.However,although dielectric materials can concentrate and manipulate light at the nanoscale,they cannot provide sufficient photothermal efficiency in a direct absorption solar collector.Combining plasmonic metal nanoparticles with dielectric nanostructures enables the fabrication of hybrid nanomaterials with excellent photothermal performance.This study presents a novel approach involving uniformly adhering plasmonic gold nanoparticles onto dielectric silicon nanoparticles to enhance the absorption peak,leading to a substantial enhancement of photothermal conversion efficiency.The results demonstrate that the absorption peak of silicon-gold hybrid nanoparticles exceeds that of pure silicon nanoparticles,achieving a 38%increase in photothermal conversion efficiency within a 10 ppm aqueous solution under a 20 mm optical path.The coupling of localized surface plasmon resonance and quadrupole resonance effects enhances the electric field,causing a temperature rise in both the hybrid nanoparticles and the surrounding aqueous solution.Nanostructural modulation studies reveal that the photothermal efficiency of silicon-gold hybrid nanoparticles is positively correlated with gold nanoparticle size but negatively correlated with silicon nanoparticle size.Combining multiple plasmonic nanoparticles with dielectric materials can effectively enhance photothermal performance and hold great application potential in direct absorption solar collectors and solar thermal utilization.
基金financial supports from National Key Research and Development Program of China(2023YFB3209500)National Natural Science Foundation of China(NSFC)(12274052 and 62171076)+1 种基金Fundamental Research Funds for the Central Universities(DUT24ZD203)Bolian Research Funds of Dalian Maritime University and Fundamental Research Funds for the Central Universities(3132024605).
文摘Accurate and real-time detection of hydrogen(H_(2))is essential for ensuring energy security.Fiber-optic H_(2) sensors are gaining attention for their integration and remote sensing capabilities.However,they face challenges,including complex fabrication processes and limited response times.Here,we propose a fiber-optic H_(2) sensing tip based on Tamm plasmon polariton(TPP)resonance,consisting of a multilayer metal/dielectric Bragg reflector deposited directly on the fiber end facet,simplifying the fabrication process.The fiber-optic TPP(FOTPP)tip exhibits both TPP and multiple Fabry-Perot(FP)resonances simultaneously,with the TPP employed for highly sensitive H_(2) detection.Compared to FP resonance,TPP exhibits more than twice the sensitivity under the same structural dimension without cavity geometry deformation.The excellent performance is attributed to alterations in phase-matching conditions,driven by changes in penetration depth of TPP.Furthermore,the FP mode is utilized to achieve an efficient photothermal effect to catalyze the reaction between H_(2) and the FOTPP structure.Consequently,the response and recovery speeds of the FOTPP tip under resonance-enhanced photothermal assistance are improved by 6.5 and 2.1 times,respectively.Our work offers a novel strategy for developing TPP-integrated fiber-optic tips,refines the theoretical framework of photothermal-assisted detection systems,and provides clear experimental evidence.
基金upported by the Guangdong Provincial Pearl River Talents Program(Grant No.2019ZT08Z779)the National Natural Science Foundation of China(Grant Nos.U21A20509 and 62205124).
文摘Metal micro-nano grating has received much attention due to its ability to provide high-efficiency light absorption.However,the current research scales of these metal gratings are focused on subwavelengths,and little attention has been paid to the absorption properties of metal gratings at other scales.We investigate the absorption properties of metal gratings based on surface plasmon resonance(SPR)across the scales from superwavelength to subwavelength.Under grazing incidence,we observe continuous strong absorption phenomena from superwavelength to subwavelength Al triangle-groove gratings(TGGs).Perfect absorption is realized at the subwavelength scale,whereas the maximum absorption at all other scales exceeds 74%.The electric field distribution gives the mechanism of the strong absorption phenomenon attributed to SPR on the surface of Al TGGs at different scales.In particular,subwavelength Al TGGs have perfectly symmetric absorption properties for different blaze angles,and the symmetry is gradually broken as the grating period’s scale increases.Furthermore,taking Al gratings with varying groove shapes for example,we extend the equivalence rule of grating grooves to subwavelength from near-wavelength and explain the symmetric absorption properties in Al TGGs.We unify the research of metal grating absorbers outside the subwavelength scale to a certain extent,and these findings also open new perspectives for the design of metal gratings in the future.
基金supported by the National Natural Science Foundation of China(No.52276094)the Education Project of Hunan Provincial Department(Nos.20B602 and 22C0112)+2 种基金the Industry University Education Cooperation Project(No.230803117185211)the Research Project on Teaching Reform in Ordinary Undergraduate Universities in Hunan Province(No.202401000142)the Natural Science Foundation of Hunan Province(No.2020JJ4935)。
文摘There is limited amount of research on surface plasmon resonance(SPR)sensors with self-referencing capabilities which are based on dielectric gratings.In the short-wavelength range,a metal grating sensor is capable of simultaneously measuring liquid refractive index under proposed temperature.A fabricated gold grating is placed on one side of a thin gold film for refractive index measurement,while the other with polydimethylsiloxane(PDMS)is deposited on the other side for temperature measurement.We use finite element analysis to research its sensing characteristics.Due to the high refractive index sensitivity of SPR sensors and thermo-optic coefficient of PDMS,we discovered the maximum spectral sensitivity of the sensor is 564 nm/RIU and-50 pm/℃when the liquid refractive index ranges from 1.30 to 1.40 with temperature ranging from 0℃ to 100℃.Numerical results indicate that there may not be mutual interference between two channels for measuring refractive index and temperature,which reduces the complexity of sensor measurements.
基金supported by the National Natural Science Foundation of China(Nos.52372090 and 52073177)the National Natural Science Foundation of Guangdong,China(No.2023A1515010947)Shenzhen Basic Research Program(No.JCYJ20220531102207017).
文摘Piezoelectric effect,plasma effect and semiconductor heterostructure are important strategies for enhanced photocatalytic performance.Herein,we developed a novel heterostructure piezoelectric photocatalyst,Ag/Ag_(2)S/BiFeO_(3)(AAS/BFO),for photocatalytic degradation of ciprofloxacin from water.Experimental results verified the enhancement of combining heterostructure piezoelectric polarization effect,which promotes efficient migration and separation of photogenerated carriers due to the localized surface plasmon resonance effect of Ag nanoparticles.Additionally,the introduction of Ag_(2)S constructs a new heterostructure,that enhances the electron transport rate and improves the separation efficiency on electron-hole pairs.Under ultrasonic stimulation and visible light irradiation,the degradation efficiencies of 15%-AAS/BFO towards ciprofloxacin,methyl orange and methylene blue are significantly enhanced compared to pure BFO fibers.The demonstrated AAS/BFO material based on the synergistic piezoelectric effect and plasmon heterostructure shows potential in efficient organic pollutants water treatment and transforming mechanical energy into chemical energy.
基金supported in part by the Natural Science Foundation of Tianjin(No.19JCYBJC16100)the Tianjin Innovation and Entrepreneurship Training Program(No.202210060027)。
文摘A triple-band miniaturized end-fire antenna based on the odd modes of spoof surface plasmonic polariton(SSPP)waveguide resonator is proposed in this paper.To meet the ever increasing demand for more communication channels and less antenna sizes,multi-band antennas are currently under intensive investigation.By a novel feeding method,three odd modes are excited on an SSPP waveguide resonator,which performs as an end-fire antenna operating at three bands,7.15-7.26 GHz,11.6-12.2 GHz and 13.5-13.64 GHz.It exhibits reasonably high and stable maximum gains of 5.26 dBi,7.97 dBi and 10.1 dBi and maximum efficiencies of 64%,92%and 98%at the three bands,respectively.Moreover,in the second band,the main beam angle shows a frequency dependence with a total scanning angle of 19°.The miniaturized triple-band antenna has a great potential in wireless communication systems,satellite communication and radar systems.
基金supported by the National Key R&D Program of China(Grant No.2021YFA1202902)the National Natural Science Foundation of China(Grant Nos.12374292 and 12074244)B.L.acknowledges support from the Development Scholarship for Outstanding Ph.D.of Shanghai Jiao Tong University.J.K.acknowledges support from the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(Grant No.NRF-RS-2024-00454528).
文摘A Luttinger liquid is a theoretical model describing interacting electrons in one-dimensional(1D)conductors.While individual 1D conductors have shown interesting Luttinger-liquid behaviors such as spin-charge separation and power-law spectral density,the more interesting phenomena predicted in coupled Luttinger liquids of neighboring 1D conductors have been rarely observed due to the difficulty in creating such structures.Recently,we have successfully grown close-packed carbon nanotube(CNT)arrays with uniform chirality,providing an ideal material system for studying the coupled Luttinger liquids.Here,we report on the observation of tunable hyperbolic plasmons in the coupled Luttinger liquids of CNT arrays using scanning near-field optical microscopy.These hyperbolic plasmons,resulting from the conductivity anisotropy in the CNT array,exhibit strong spatial confinement,in situ tunability,and a wide spectral range.Despite their hyperbolic wavefronts,the plasmon propagation in the axial direction still adheres to the Luttinger-liquid theory.Our work not only demonstrates a fascinating phenomenon in coupled Luttinger liquids for fundamental physics exploration,but also provides a highly confined and in situ tunable hyperbolic plasmon in close-packed CNT arrays for future nanophotonic devices and circuits.
文摘Devising S-scheme heterostructure is considered as a cutting-edge strategy for advanced photocatalysts with effectively segregated photo-carriers and prominent redox potential for emerging organic pollutants control.Herein,an S-scheme Ag_(2)CO_(3)/C_(3)N_(5) heterojunction photocatalyst was developed via a simple in situ chemical deposition procedure,and further photoreduction operation made metallic Ag(size:3.5–12.5 nm)being in situ formed on Ag_(2)CO_(3)/C_(3)N_(5) for a plasmonic S-scheme Ag/Ag_(2)CO_(3)/C_(3)N_(5) heterojunction photocatalyst.Consequently,Ag/Ag_(2)CO_(3)/C_(3)N_(5) manifests pronouncedly upgraded photocatalytic performance toward oxytetracycline degradation with a superior photoreaction rate constant of 0.0475 min‒1,which is 13.2,3.9 and 2.2 folds that of C_(3)N_(5),Ag_(2)CO_(3),and Ag_(2)CO_(3)/C_(3)N_(5),respectively.As evidenced by comprehensive characterizations and density functional theory calculations,the localized surface plasmon resonance effect of metallic Ag and the unique S-scheme charge transfer mechanism in 0D/0D/2D Ag/Ag_(2)CO_(3)/C_(3)N_(5) collaboratively strengthen the visible-light absorption,and facilitate the effective separation of powerful charge carriers,thereby significantly promoting the generation of reactive species like·OH^(-),h^(+)and·O_(2)^(-)for efficient oxytetracycline destruction.Moreover,four consecutive cycles demonstrate the reusability of Ag/Ag_(2)CO_(3)/C_(3)N_(5).Furthermore,the authentic water purification tests affirm its practical application potential.This work not only provides a candidate strategy for advancing S-scheme heterojunction photocatalysts but also makes a certain contribution to water decontamination.
文摘Nano-optics is an emergent research field in physics that appeared in the 1980s,which deals with light–matter optical interactions at the nanometer scale.In early studies of nano-optics,the main concern focus is to obtain higher optical resolution over the diffraction limit.The researches of near-field imaging and spectroscopy based on scanning near-field optical microscopy(SNOM)are developed.The exploration of improving SNOM probe for near-field detection leads to the emergence of surface plasmons.In the sense of resolution and wider application,there has been a significant transition from seeking higher resolution microscopy to plasmonic near-field modulations in the nano-optics community during the nano-optic development.Nowadays,studies of nano-optics prefer the investigation of plasmonics in different material systems.In this article,the history of the development of near-field optics is briefly reviewed.The difficulties of conventional SNOM to achieve higher resolution are discussed.As an alternative solution,surface plasmons have shown the advantages of higher resolution,wider application,and flexible nano-optical modulation for new devices.The typical studies in different periods are introduced and characteristics of nano-optics in each stage are analyzed.In this way,the evolution progress from near-field optics to plasmonics of nano-optics research is presented.The future development of nano-optics is discussed then.
