Measured surface localization （MSL） is one of the key essentials for the assessment of form error in pre- cision manufacturing. Currently, the researches on MSL have focused on the corresponding relation search betw...Measured surface localization （MSL） is one of the key essentials for the assessment of form error in pre- cision manufacturing. Currently, the researches on MSL have focused on the corresponding relation search between two surfaces, the performance improvement of localization algorithms and the uncertainty analysis of localization. However, low efficiency, limitation of localization algo- rithms and mismatch of multiple similarities of feature points with no prior are the common disadvantages for MSL. In order to match feature points quickly and fulfill MSL efficiently, this paper presents a new localization approach for measured surfaces by extracting the generic umbilics and estimating their single complex variables, describing the match methods of ambiguous relation at umbilics, presenting the initial localization process of one pair matched points, refining MSL on the basis of obtained closet points for some measured points by the improvement directed projection method. In addition, the proposed algorithm is simulated in two different types of surfaces,two different localization types and multiple similar sur- faces, also tested with the part of B-spline surface machined and bottle mould with no knowledge, finally the initial and accurate rigid body transformation matrix, localization errors between two surfaces and execution time are got. The experimental results show that the pro- posed method is feasible, more accurate in localization and high in efficiency. The proposed research can not only improve the accuracy and performance of form error assessment, but also provide an effective guideline for the integration of different types of measured surfaces.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
An optical biosensor is a specialized analytical device that utilizes the principles of optics and light in bimolecular processes.Localized surface plasmon resonance(LSPR)is a phenomenon in the realm of nanophotonics ...An optical biosensor is a specialized analytical device that utilizes the principles of optics and light in bimolecular processes.Localized surface plasmon resonance(LSPR)is a phenomenon in the realm of nanophotonics that occurs when metallic nanoparticles(NPs)or nanostructures interact with incident light.Conversely,surface-enhanced Raman spectroscopy(SERS)is an influential analytical technique based on Raman scattering,wherein it amplifies the Raman signals of molecules when they are situated near specific and specially designed nanostructures.A detailed exploration of the recent groundbreaking developments in optical biosensors employing LSPR and SERS technologies has been thoroughly discussed along with their underlying principles and the working mechanisms.A biosensor chip has been created,featuring a high-density deposition of gold nanoparticles(AuNPs)under varying ligand concentration and reaction duration on the substrate.An ordinary description,along with a visual illustration,has been thoroughly provided for concepts such as a sensogram,refractive index shift,surface plasmon resonance(SPR),and the evanescent field,Rayleigh scattering,Raman scattering,as well as the electromagnetic enhancement and chemical enhancement.LSPR and SERS both have advantages and disadvantages,but widely used SERS has some advantages over LSPR,like chemical specificity,high sensitivity,multiplexing,and versatility in different fields.This review confirms and elucidates the significance of different disease biomarker identification.LSPR and SERS both play a vital role in the detection of various types of cancer,such as cervical cancer,ovarian cancer,endometrial cancer,prostate cancer,colorectal cancer,and brain tumors.This proposed optical biosensor offers potential applications for early diagnosis and monitoring of viral disease,bacterial infectious diseases,fungal diseases,diabetes,and cardiac disease biosensing.LSPR and SERS provide a new direction for environmental monitoring,food safety,refining impurities from water samples,and lead detection.The understanding of these biosensors is still limited and challenging.展开更多
Recent breakthroughs in the field of non-Hermitian physics present unprecedented opportunities,from fundamental theories to cutting-edge applications such as multimode lasers,unconventional wave transport,and high-per...Recent breakthroughs in the field of non-Hermitian physics present unprecedented opportunities,from fundamental theories to cutting-edge applications such as multimode lasers,unconventional wave transport,and high-performance sensors.The exceptional point,a spectral singularity widely existing in non-Hermitian systems,provides an indispensable route to enhance the sensitivity of optical detection.However,the exceptional point of the forementioned systems is set once the system is built or fabricated,and machining errors make it hard to reach such a state precisely.To this end,we develop a highly tunable and reconfigurable exceptional point system,i.e.,a single spoof plasmonic resonator suspended above a substrate and coupled with two freestanding Rayleigh scatterers.Our design offers great flexibility to control exceptional point states,enabling us to dynamically reconfigure the exceptional point formed by various multipolar modes across a broadband frequency range.Specifically,we experimentally implement five distinct exceptional points by precisely manipulating the positions of two movable Rayleigh scatterers.In addition,the enhanced perturbation strength offers remarkable sensitivity enhancement for detecting deep-subwavelength particles with the minimum dimension down to 0.001λ(withλto be the free-space wavelength).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
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
MXene is an emerging class of two-dimensional(2D)layered transition metal carbides or nitrides.Due to the highly tunable components and surface functional groups,it holds great potential in electrocatalytic hydrogen e...MXene is an emerging class of two-dimensional(2D)layered transition metal carbides or nitrides.Due to the highly tunable components and surface functional groups,it holds great potential in electrocatalytic hydrogen evolution reaction(HER).However,MXene nanosheet suffers from a strong tendency to restack and a lack of active edge sites.In this work,the porous Ti_(3)C_(2)T_(x)was synthesized by an oxidation and etching two-step strategy and then characterized by a series of spectroscopic techniques.The obtained porous Ti_(3)C_(2)T_(x)possesses a large number of in-plane pores.This not only creates abundant active edge sites but also enhances the mass transfer and increases the accessibility of the active sites.Compared with Ti_(3)C_(2)T_(x),in a 0.5 mol/L H_(2)SO_(4)electrolyte,the porous Ti_(3)C_(2)T_(x)shows a 65.6%higher electrochemical surface area(ECSA)(440 mF/cm^(2)),a 95.2%lower charge transfer resistance(12.8Ω),and a 69.8%lower Tafel slope(144 mV/dec),and thus exhibits lower overpotential with good stability at a current density of 10 mA/cm^(2).At the same time,the HER performance of the porous Ti_(3)C_(2)T_(x)can be further enhanced by near-infrared laser irradiation based on the localized surface plasmon resonance effect.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
Localized surface plasmon resonance (LSPR) enhanced photocatalysis has fascinated much interest and considerable efforts have been devoted toward the development of plasmonic photocatalysts. In the past decades, noble...Localized surface plasmon resonance (LSPR) enhanced photocatalysis has fascinated much interest and considerable efforts have been devoted toward the development of plasmonic photocatalysts. In the past decades, noble metal nanoparticles (Au and Ag) with LSPR feature have found wide applications in solar energy conversion. Numerous metal-based photocatalysts have been proposed including metal/semiconductor heterostructures and plasmonic bimetallic or multimetallic nanostructures. However, high cost and scarce reserve of noble metals largely limit their further practical use, which drives the focus gradually shift to low-cost and abundant nonmetallic nanostructures. Recently, various heavily doped semiconductors (such as WO_(3-x), MoO_(3-x), Cu_(2-x)S, TiN) have emerged as potential alternatives to costly noble metals for efficient photocatalysis due to their strong LSPR property in visible-near infrared region. This review starts with a brief introduction to LSPR property and LSPR-enhanced photocatalysis, the following highlights recent advances of plasmonic photocatalysts from noble metal to semiconductor-based plasmonic nanostructures. Their synthesis methods and promising applicability in plasmon-driven photocatalytic reactions such as water splitting, CO_(2) reduction and pollution decomposition are also summarized in details. This review is expected to give guidelines for exploring more efficient plasmonic systems and provide a perspective on development of plasmonic photocatalysis.展开更多
The subwavelength confinement feature of localized surface plasmon resonance（LSPR） allows plasmonic nanostructures to be functionalized as powerful platforms for detecting various molecular analytes as well as weak ...The subwavelength confinement feature of localized surface plasmon resonance（LSPR） allows plasmonic nanostructures to be functionalized as powerful platforms for detecting various molecular analytes as well as weak processes with nanoscale spatial resolution. One of the main goals of this field of research is to lower the absolute limit-of-detection（LOD）of LSPR-based sensors. This involves the improvement of（i） the figure-of-merit associated with structural parameters such as the size, shape and interparticle arrangement and,（ii） the spectral resolution. The latter involves advanced target identification and noise reduction techniques. By highlighting the strategies for improving the LOD, this review introduces the fundamental principles and recent progress of LSPR sensing based on different schemes including 1） refractometric sensing realized by observing target-induced refractive index changes, 2） plasmon rulers based on target-induced relative displacement of coupled plasmonic structures, 3） other relevant LSPR-based sensing schemes including chiral plasmonics,nanoparticle growth, and optomechanics. The ultimate LOD and the future trends of these LSPR-based sensing are also discussed.展开更多
This paper presents a method of generating a parametric G^n blending surfacebased on reparameterizing the partial surface patches in the base surfaces on the basis of ErichHartmann method. This method is expressed as ...This paper presents a method of generating a parametric G^n blending surfacebased on reparameterizing the partial surface patches in the base surfaces on the basis of ErichHartmann method. This method is expressed as follows Firstly, the partial region near contact curvesin both base surfaces is reparameterized. The contact curves are used as the boundaries of thereparameterized partial region respectively. The reparameterized partial region in two base surfacesis called the reparameterized local base surfaces. Then the parametric G^n blending surface isgenerated by a linear combination of the reparameterized local base surface patches depending on oneof the common parameters. Therefore, generating a Parametric G^n Blending Surface between two basesurfaces is translated into generating a Parametric G^n Blending Surface between the tworeparameterized local base surfaces. This paper illustrates the method to generate the G^n blendingsurface with some constraints by generating a G^2 blending surface between the aerofoil and the bodyof a missile with the constraints of the forward and rear fringe curves. When the G^n blendingsurface with some constraints is generated, the partial region near contact curves in both basesurfaces is reparameterized, and the scale factors, offset, balance factor and thumb weight aredefined by meeting the constraints through using an optimization method. Then the parametric G^nblending surface is generated by the linear combination of the reparameterized local base surfacepatches. The shape of the blending surface can be adjusted by changing the size of thereparameterized local base surface patches.展开更多
The photocatalytic reduction of CO2 with H2O to fuels and chemicals using solar energy is one of the most attractive but highly difficult routes.Thus far,only a very limited number of photocatalysts has been reported ...The photocatalytic reduction of CO2 with H2O to fuels and chemicals using solar energy is one of the most attractive but highly difficult routes.Thus far,only a very limited number of photocatalysts has been reported to be capable of catalyzing the photocatalytic reduction of CO2 under visible light.The utilization of the localized surface plasmon resonance(LSPR)phenomenon is an attractive strategy for developing visible-light photocatalysts.Herein,we have succeeded in synthesizing plasmonic MoO3?x-TiO2 nanocomposites with tunable LSPR by a simple solvothermal method.The well-structured nanocomposite containing two-dimensional(2D)molybdenum oxide(MoO3?x)nanosheets and one-dimensional(1D)titanium oxide nanotubes(TiO2-NT)showed LSPR absorption band in the visible-light region,and the incorporation of TiO2-NT significantly enhanced the LSPR absorption band.The MoO3?x-TiO2-NT nanocomposite is promising for application in the photocatalytic reduction of CO2 with H2O under visible light irradiation.展开更多
The cluster-shaped plasmonic nanostructures are used to manage the incident light inside an ultra-thin silicon solar cell.Here we simulate spherical,conical,pyramidal,and cylindrical nanoparticles in a form of a clust...The cluster-shaped plasmonic nanostructures are used to manage the incident light inside an ultra-thin silicon solar cell.Here we simulate spherical,conical,pyramidal,and cylindrical nanoparticles in a form of a cluster at the rear side of a thin silicon cell,using the finite difference time domain(FDTD)method.By calculating the optical absorption and hence the photocurrent,it is shown that the clustering of nanoparticles significantly improves them.The photocurrent enhancement is the result of the plasmonic effects of clustering the nanoparticles.For comparison,first a cell with a single nanoparticle at the rear side is evaluated.Then four smaller nanoparticles are put around it to make a cluster.The photocurrents of 20.478 mA/cm2,23.186 mA/cm2,21.427 mA/cm2,and 21.243 mA/cm2 are obtained for the cells using clustering conical,spherical,pyramidal,cylindrical NPs at the backside,respectively.These values are 13.987 mA/cm2,16.901 mA/cm2,16.507 mA/cm2,17.926 mA/cm2 for the cell with one conical,spherical,pyramidal,cylindrical NPs at the backside,respectively.Therefore,clustering can significantly improve the photocurrents.Finally,the distribution of the electric field and the generation rate for the proposed structures are calculated.展开更多
We investigate the sensitivity and figure of merit （FOM） of a localized surface plasmon （LSP） sensor with gold nanograting on the top of planar metallic film. The sensitivity of the localized surface plasmon senso...We investigate the sensitivity and figure of merit （FOM） of a localized surface plasmon （LSP） sensor with gold nanograting on the top of planar metallic film. The sensitivity of the localized surface plasmon sensor is 317 nm/RIU, and the FOM is predicted to be above 8, which is very high for a localized surface plasmon sensor. By employing the rigorous coupled-wave analysis （RCWA） method, we analyze the distribution of the magnetic field and find that the sensing property of our proposed system is attributed to the interactions between the localized surface plasmon around the gold nanostrips and the surface plasmon polarition on the surface of the gold planar metallic film. These findings are important for developing high FOM localized surface plasmon sensors.展开更多
The influences of the anisotropy of the outer spherically anisotropic （SA） layer on the far-field spectra and near- field enhancements of the silver nanoshells are investigated by using a modified Mie scattering the...The influences of the anisotropy of the outer spherically anisotropic （SA） layer on the far-field spectra and near- field enhancements of the silver nanoshells are investigated by using a modified Mie scattering theory. It is found that with the increase of the anisotropic value of the SA layer, the dipole resonance wavelength of the silver nanoshell first increases and then decreases, while the local field factor （LFF） reduces. With the decrease of SA layer thickness, the dipole wavelength of the silver nanoshell shows a distinct blue-shift. When the SA layer becomes very thin, the modulations of the anisotropy of the SA layer on the plasmon resonance energy and the near-field enhancement are weakened. We further find that the smaller anisotropic value of the SA layer is helpful for obtaining the larger near-field enhancement in the Ag nanoshell. The geometric average of the dielectric components of the SA layer has a stronger effect on the plasmon resonance energy of the silver nanoshell than on the near-field enhancement.展开更多
A fast and facile method of fabricating fiber-optic localized surface plasmon resonance sensors baseff on spherical gold nanoparticles was introduced in this study. The gold nanoparticles with an average diameter of 5...A fast and facile method of fabricating fiber-optic localized surface plasmon resonance sensors baseff on spherical gold nanoparticles was introduced in this study. The gold nanoparticles with an average diameter of 55 nm were synthesized via the Turkevich method and were then immobilized onto the surface of an uncladded sensor probe using a polydopamine layer. To obtain a sensor probe with high sensitivity to changes in the refractive index, a set of key optimization parameters, including the sensing length, coating time of the potydopamine layer, and coating time of the gold nanoparticles, were investigated. The sensitivity of the optimized sensor probe was 522.80 nm per refractive index unit, and the probe showed distinctive wavelength shifts when the refractive index was changed from 1.328 6 to 1.398 7. When stored in deionized water at 4 ℃, the sensor probe proved to be stable over a period of two weeks. The sensor also exhibited advantages, such as low cost, fast fabrication, and simple optical setup, which indicated its potential application in remote sensing and real-time detection.展开更多
Lanthanum hexaboride nanopartieles, with high emission electrons in cathode materials and peculiar blocking near infrared wavelengths, were applied for many aspects. Based on the quasi-static approximation of Mie theo...Lanthanum hexaboride nanopartieles, with high emission electrons in cathode materials and peculiar blocking near infrared wavelengths, were applied for many aspects. Based on the quasi-static approximation of Mie theory, the size dependent optical prop- erties of LaB6 nanoparticles were researched, such as refractive index n（ω）, extinction coefficient k（ω）, reflectivity R（ω）, absorption coefficient a（ω）, and electron energy loss L（ω）. Due to the localized surface plasmon resonance （LSPR）, the extinction coefficient k（ω） and absorption coefficient a（ω） depended on the size, and the LSPR peaks red-shifted with sizes increased, which was different from that of bulk materials. In addition, electron energy-loss spectrum L（co） showed electrons oscillation reinforced, since electrons absorbed the photon energy and generated resonance. Further, reftectivity R（ω） and refractive index n（ω） indicated that the light in near infrared region could not be propagated on the surface of LaB6 materials, which exhibited metallic behaviors. So the resonance peak of LaB6 nanoparticle was located in near-infrared region, making use of this property for solar control glazing and heat-shielding application.展开更多
In this paper,a local surface nanocrystallization technology is used for thin-walled structures with square cross sections,and an energy absorption device of two-staged combined energy absorption structure is proposed...In this paper,a local surface nanocrystallization technology is used for thin-walled structures with square cross sections,and an energy absorption device of two-staged combined energy absorption structure is proposed.In virtue of the surface nanocrystallization that enables to change the material on local positions,the structural deformation is induced and controlled to maximize the energy absorption capacity.A numerical model of the two-staged combined energy absorption structure is established,and the local surface nanocrystallization layout is optimized.The results show that the specific energy absorption of two-staged combined structure with local surface nanocrystallization can be increased by 34.36%compared with the untreated counterpart of the same material and structural shape.The ratio between the first and second peak crushing forces and the energy absorption allocation ratio between the two stages can be adjusted in the ranges of 0.26–0.55 and 0.31–0.45,respectively,which can be controlled by the local surface nanocrystallization designs.The numerical simulation and experimental results are in good agreement,which shows that the design for energy absorption device with local surface nanocrystallization is feasible and effective.展开更多
In order to enhance the p-type doping concentration in the LBSF, boron was added into the aluminum paste and boron doped local back surface field（B-LBSF） was successfully fabricated in this work. Through boron dopin...In order to enhance the p-type doping concentration in the LBSF, boron was added into the aluminum paste and boron doped local back surface field（B-LBSF） was successfully fabricated in this work. Through boron doping in the LBSF, much higher doping concentration was observed for the B-LBSF over the Al-LBSF. Higher doping concentration in the LBSF is expected to lead to better rear passivation and lower rear contact resistance. Based on one thousand pieces of solar cells for each type, it was found that the rear passivated crystalline silicon solar cells with B-LBSF showed statistical improvement in their photovoltaic properties over those with Al-LBSF.展开更多
The simulation mechanism of surface plasmon polaritons(SPPs)and localized surface plasmon(LSP)in different structures was studied,including the Au reflection grating(Au grating),Au substrate with dielectric ribbons gr...The simulation mechanism of surface plasmon polaritons(SPPs)and localized surface plasmon(LSP)in different structures was studied,including the Au reflection grating(Au grating),Au substrate with dielectric ribbons grating(Au substrate grating),and pure electric conductor(PEC)substrate with Au ribbons grating(Au ribbons grating).And the characteristics of the Smith-Purcell radiation in these structures were presented.Simulation results show that SPPs are excited on the bottom surface of Au substrate grating grooves and LSP is stimulated on the upper surface both of Au ribbons grating grooves and Au grating grooves.Owing to the irreconcilable contradiction between optimizing the grating diffraction radiation efficiency and optimizing the SPPs excitation efficiency in the Au substrate grating,only 40-times enhancement of the radiation intensity was obtained by excited SPPs.However,the LSP enhanced structure overcomes the above problem and gains much better radiation enhancement ability,with about 200-times enhancement obtained in the Au ribbons grating and more than 500-times enhancement obtained in the Au grating.The results presented here provide a way of developing miniature,integratable,tunable,high-power-density radiation sources from visible light to ultraviolet rays at room temperature.展开更多
基金Supported by Science and Technology Supporting Projects of China(Grant No.2015BAF27B01)Sichuan Provincial Science and Technology Supporting Program of China(Grant Nos.2014GZ0119,2017GZ0350)Open Research Fund of Key Laboratory of Manufacturing and Automation,Xihua University(Grant No.S2jj2013-042)
文摘Measured surface localization （MSL） is one of the key essentials for the assessment of form error in pre- cision manufacturing. Currently, the researches on MSL have focused on the corresponding relation search between two surfaces, the performance improvement of localization algorithms and the uncertainty analysis of localization. However, low efficiency, limitation of localization algo- rithms and mismatch of multiple similarities of feature points with no prior are the common disadvantages for MSL. In order to match feature points quickly and fulfill MSL efficiently, this paper presents a new localization approach for measured surfaces by extracting the generic umbilics and estimating their single complex variables, describing the match methods of ambiguous relation at umbilics, presenting the initial localization process of one pair matched points, refining MSL on the basis of obtained closet points for some measured points by the improvement directed projection method. In addition, the proposed algorithm is simulated in two different types of surfaces,two different localization types and multiple similar sur- faces, also tested with the part of B-spline surface machined and bottle mould with no knowledge, finally the initial and accurate rigid body transformation matrix, localization errors between two surfaces and execution time are got. The experimental results show that the pro- posed method is feasible, more accurate in localization and high in efficiency. The proposed research can not only improve the accuracy and performance of form error assessment, but also provide an effective guideline for the integration of different types of measured surfaces.
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.
文摘An optical biosensor is a specialized analytical device that utilizes the principles of optics and light in bimolecular processes.Localized surface plasmon resonance(LSPR)is a phenomenon in the realm of nanophotonics that occurs when metallic nanoparticles(NPs)or nanostructures interact with incident light.Conversely,surface-enhanced Raman spectroscopy(SERS)is an influential analytical technique based on Raman scattering,wherein it amplifies the Raman signals of molecules when they are situated near specific and specially designed nanostructures.A detailed exploration of the recent groundbreaking developments in optical biosensors employing LSPR and SERS technologies has been thoroughly discussed along with their underlying principles and the working mechanisms.A biosensor chip has been created,featuring a high-density deposition of gold nanoparticles(AuNPs)under varying ligand concentration and reaction duration on the substrate.An ordinary description,along with a visual illustration,has been thoroughly provided for concepts such as a sensogram,refractive index shift,surface plasmon resonance(SPR),and the evanescent field,Rayleigh scattering,Raman scattering,as well as the electromagnetic enhancement and chemical enhancement.LSPR and SERS both have advantages and disadvantages,but widely used SERS has some advantages over LSPR,like chemical specificity,high sensitivity,multiplexing,and versatility in different fields.This review confirms and elucidates the significance of different disease biomarker identification.LSPR and SERS both play a vital role in the detection of various types of cancer,such as cervical cancer,ovarian cancer,endometrial cancer,prostate cancer,colorectal cancer,and brain tumors.This proposed optical biosensor offers potential applications for early diagnosis and monitoring of viral disease,bacterial infectious diseases,fungal diseases,diabetes,and cardiac disease biosensing.LSPR and SERS provide a new direction for environmental monitoring,food safety,refining impurities from water samples,and lead detection.The understanding of these biosensors is still limited and challenging.
基金supported by the National Natural Science Foundation of China(Grant Nos.61871215,61771238,and 61701246)the National Key Research and Development Program of China(Grant No.2022YFA1404903)+9 种基金the Fund of Qing Lan Project of Jiangsu Province(Grant No.1004-YQR22031)the Six Talent Peaks Project in Jiangsu Province(Grant No.2018-GDZB-009)the Fund of Prospective Layout of Scientific Research for NUAA(Nanjing University of Aeronautics and Astronautics)(Grant Nos.1004-ILA22002 and 1004-ILA22068)the Research and Practice Innovation Program of Nanjing University of Aeronautics and Astronautics(Grant No.xcxjh20210408)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX22_0364)the Fundamental Research Funds for the Central Universities,NUAA(Grant No.NS2023022)the Nanjing University of Aeronautics and Astronautics Startup Grant(Grant No.1004-YQR23031)the Distinguished Professor Fund of Jiangsu Province(Grant No.1004-YQR24010)Fundamental Research Funds for the Central Universities,NUAA(No.NE2024007)the Singapore National Research Foundation Competitive Research Program(NRF-CRP22-2019-0006).
文摘Recent breakthroughs in the field of non-Hermitian physics present unprecedented opportunities,from fundamental theories to cutting-edge applications such as multimode lasers,unconventional wave transport,and high-performance sensors.The exceptional point,a spectral singularity widely existing in non-Hermitian systems,provides an indispensable route to enhance the sensitivity of optical detection.However,the exceptional point of the forementioned systems is set once the system is built or fabricated,and machining errors make it hard to reach such a state precisely.To this end,we develop a highly tunable and reconfigurable exceptional point system,i.e.,a single spoof plasmonic resonator suspended above a substrate and coupled with two freestanding Rayleigh scatterers.Our design offers great flexibility to control exceptional point states,enabling us to dynamically reconfigure the exceptional point formed by various multipolar modes across a broadband frequency range.Specifically,we experimentally implement five distinct exceptional points by precisely manipulating the positions of two movable Rayleigh scatterers.In addition,the enhanced perturbation strength offers remarkable sensitivity enhancement for detecting deep-subwavelength particles with the minimum dimension down to 0.001λ(withλto be the free-space wavelength).
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 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.
文摘MXene is an emerging class of two-dimensional(2D)layered transition metal carbides or nitrides.Due to the highly tunable components and surface functional groups,it holds great potential in electrocatalytic hydrogen evolution reaction(HER).However,MXene nanosheet suffers from a strong tendency to restack and a lack of active edge sites.In this work,the porous Ti_(3)C_(2)T_(x)was synthesized by an oxidation and etching two-step strategy and then characterized by a series of spectroscopic techniques.The obtained porous Ti_(3)C_(2)T_(x)possesses a large number of in-plane pores.This not only creates abundant active edge sites but also enhances the mass transfer and increases the accessibility of the active sites.Compared with Ti_(3)C_(2)T_(x),in a 0.5 mol/L H_(2)SO_(4)electrolyte,the porous Ti_(3)C_(2)T_(x)shows a 65.6%higher electrochemical surface area(ECSA)(440 mF/cm^(2)),a 95.2%lower charge transfer resistance(12.8Ω),and a 69.8%lower Tafel slope(144 mV/dec),and thus exhibits lower overpotential with good stability at a current density of 10 mA/cm^(2).At the same time,the HER performance of the porous Ti_(3)C_(2)T_(x)can be further enhanced by near-infrared laser irradiation based on the localized surface plasmon resonance effect.
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.
基金supported by the National Natural Science Foundation of China (Nos. 11904133, 51872125)Guangdong Natural Science Funds for Distinguished Young Scholar (No. 2018B030306004) and GDUPS (2018)+1 种基金the Fundamental Research Funds for the Central Universities (No. 21619322)Regional Joint Foundation in Guangdong Province (No. 2019A1515110210)。
文摘Localized surface plasmon resonance (LSPR) enhanced photocatalysis has fascinated much interest and considerable efforts have been devoted toward the development of plasmonic photocatalysts. In the past decades, noble metal nanoparticles (Au and Ag) with LSPR feature have found wide applications in solar energy conversion. Numerous metal-based photocatalysts have been proposed including metal/semiconductor heterostructures and plasmonic bimetallic or multimetallic nanostructures. However, high cost and scarce reserve of noble metals largely limit their further practical use, which drives the focus gradually shift to low-cost and abundant nonmetallic nanostructures. Recently, various heavily doped semiconductors (such as WO_(3-x), MoO_(3-x), Cu_(2-x)S, TiN) have emerged as potential alternatives to costly noble metals for efficient photocatalysis due to their strong LSPR property in visible-near infrared region. This review starts with a brief introduction to LSPR property and LSPR-enhanced photocatalysis, the following highlights recent advances of plasmonic photocatalysts from noble metal to semiconductor-based plasmonic nanostructures. Their synthesis methods and promising applicability in plasmon-driven photocatalytic reactions such as water splitting, CO_(2) reduction and pollution decomposition are also summarized in details. This review is expected to give guidelines for exploring more efficient plasmonic systems and provide a perspective on development of plasmonic photocatalysis.
基金Project supported by the National Key Basic Research Program(Grant No.2015CB932400)the National Key Research and Development Program of China(Grant Nos.2017YFA0205800 and 2017YFA0303504)the National Natural Science Foundation of China(Grant Nos.11674255 and 11674256)
文摘The subwavelength confinement feature of localized surface plasmon resonance（LSPR） allows plasmonic nanostructures to be functionalized as powerful platforms for detecting various molecular analytes as well as weak processes with nanoscale spatial resolution. One of the main goals of this field of research is to lower the absolute limit-of-detection（LOD）of LSPR-based sensors. This involves the improvement of（i） the figure-of-merit associated with structural parameters such as the size, shape and interparticle arrangement and,（ii） the spectral resolution. The latter involves advanced target identification and noise reduction techniques. By highlighting the strategies for improving the LOD, this review introduces the fundamental principles and recent progress of LSPR sensing based on different schemes including 1） refractometric sensing realized by observing target-induced refractive index changes, 2） plasmon rulers based on target-induced relative displacement of coupled plasmonic structures, 3） other relevant LSPR-based sensing schemes including chiral plasmonics,nanoparticle growth, and optomechanics. The ultimate LOD and the future trends of these LSPR-based sensing are also discussed.
文摘This paper presents a method of generating a parametric G^n blending surfacebased on reparameterizing the partial surface patches in the base surfaces on the basis of ErichHartmann method. This method is expressed as follows Firstly, the partial region near contact curvesin both base surfaces is reparameterized. The contact curves are used as the boundaries of thereparameterized partial region respectively. The reparameterized partial region in two base surfacesis called the reparameterized local base surfaces. Then the parametric G^n blending surface isgenerated by a linear combination of the reparameterized local base surface patches depending on oneof the common parameters. Therefore, generating a Parametric G^n Blending Surface between two basesurfaces is translated into generating a Parametric G^n Blending Surface between the tworeparameterized local base surfaces. This paper illustrates the method to generate the G^n blendingsurface with some constraints by generating a G^2 blending surface between the aerofoil and the bodyof a missile with the constraints of the forward and rear fringe curves. When the G^n blendingsurface with some constraints is generated, the partial region near contact curves in both basesurfaces is reparameterized, and the scale factors, offset, balance factor and thumb weight aredefined by meeting the constraints through using an optimization method. Then the parametric G^nblending surface is generated by the linear combination of the reparameterized local base surfacepatches. The shape of the blending surface can be adjusted by changing the size of thereparameterized local base surface patches.
文摘The photocatalytic reduction of CO2 with H2O to fuels and chemicals using solar energy is one of the most attractive but highly difficult routes.Thus far,only a very limited number of photocatalysts has been reported to be capable of catalyzing the photocatalytic reduction of CO2 under visible light.The utilization of the localized surface plasmon resonance(LSPR)phenomenon is an attractive strategy for developing visible-light photocatalysts.Herein,we have succeeded in synthesizing plasmonic MoO3?x-TiO2 nanocomposites with tunable LSPR by a simple solvothermal method.The well-structured nanocomposite containing two-dimensional(2D)molybdenum oxide(MoO3?x)nanosheets and one-dimensional(1D)titanium oxide nanotubes(TiO2-NT)showed LSPR absorption band in the visible-light region,and the incorporation of TiO2-NT significantly enhanced the LSPR absorption band.The MoO3?x-TiO2-NT nanocomposite is promising for application in the photocatalytic reduction of CO2 with H2O under visible light irradiation.
文摘The cluster-shaped plasmonic nanostructures are used to manage the incident light inside an ultra-thin silicon solar cell.Here we simulate spherical,conical,pyramidal,and cylindrical nanoparticles in a form of a cluster at the rear side of a thin silicon cell,using the finite difference time domain(FDTD)method.By calculating the optical absorption and hence the photocurrent,it is shown that the clustering of nanoparticles significantly improves them.The photocurrent enhancement is the result of the plasmonic effects of clustering the nanoparticles.For comparison,first a cell with a single nanoparticle at the rear side is evaluated.Then four smaller nanoparticles are put around it to make a cluster.The photocurrents of 20.478 mA/cm2,23.186 mA/cm2,21.427 mA/cm2,and 21.243 mA/cm2 are obtained for the cells using clustering conical,spherical,pyramidal,cylindrical NPs at the backside,respectively.These values are 13.987 mA/cm2,16.901 mA/cm2,16.507 mA/cm2,17.926 mA/cm2 for the cell with one conical,spherical,pyramidal,cylindrical NPs at the backside,respectively.Therefore,clustering can significantly improve the photocurrents.Finally,the distribution of the electric field and the generation rate for the proposed structures are calculated.
基金Project supported by the National Key Research Program of China(Grant No.2011ZX01015-001)
文摘We investigate the sensitivity and figure of merit （FOM） of a localized surface plasmon （LSP） sensor with gold nanograting on the top of planar metallic film. The sensitivity of the localized surface plasmon sensor is 317 nm/RIU, and the FOM is predicted to be above 8, which is very high for a localized surface plasmon sensor. By employing the rigorous coupled-wave analysis （RCWA） method, we analyze the distribution of the magnetic field and find that the sensing property of our proposed system is attributed to the interactions between the localized surface plasmon around the gold nanostrips and the surface plasmon polarition on the surface of the gold planar metallic film. These findings are important for developing high FOM localized surface plasmon sensors.
基金Project supported by the National Basic Research Program of China(Grant No.2012CB921504)the National Natural Science Foundation of China(Grant Nos.10904052,11174113,and 11104319)+1 种基金the Jiangsu Planned Projects for Postdoctoral Research Funds,China(Grant No.1002075C)the Senior Talent Foundation of Jiangsu University,China(Grant No.09JDG073)
文摘The influences of the anisotropy of the outer spherically anisotropic （SA） layer on the far-field spectra and near- field enhancements of the silver nanoshells are investigated by using a modified Mie scattering theory. It is found that with the increase of the anisotropic value of the SA layer, the dipole resonance wavelength of the silver nanoshell first increases and then decreases, while the local field factor （LFF） reduces. With the decrease of SA layer thickness, the dipole wavelength of the silver nanoshell shows a distinct blue-shift. When the SA layer becomes very thin, the modulations of the anisotropy of the SA layer on the plasmon resonance energy and the near-field enhancement are weakened. We further find that the smaller anisotropic value of the SA layer is helpful for obtaining the larger near-field enhancement in the Ag nanoshell. The geometric average of the dielectric components of the SA layer has a stronger effect on the plasmon resonance energy of the silver nanoshell than on the near-field enhancement.
基金Supported by the Ministry of Science and Technology of China(No.2012YQ090194)the National Natural Science Foundation of China(No.51473115)
文摘A fast and facile method of fabricating fiber-optic localized surface plasmon resonance sensors baseff on spherical gold nanoparticles was introduced in this study. The gold nanoparticles with an average diameter of 55 nm were synthesized via the Turkevich method and were then immobilized onto the surface of an uncladded sensor probe using a polydopamine layer. To obtain a sensor probe with high sensitivity to changes in the refractive index, a set of key optimization parameters, including the sensing length, coating time of the potydopamine layer, and coating time of the gold nanoparticles, were investigated. The sensitivity of the optimized sensor probe was 522.80 nm per refractive index unit, and the probe showed distinctive wavelength shifts when the refractive index was changed from 1.328 6 to 1.398 7. When stored in deionized water at 4 ℃, the sensor probe proved to be stable over a period of two weeks. The sensor also exhibited advantages, such as low cost, fast fabrication, and simple optical setup, which indicated its potential application in remote sensing and real-time detection.
基金supported by National Natural Science Foundation of China(60907021,60977035,60877029)Tianjin Natural Science Foundation(11JCYBJC00300)
文摘Lanthanum hexaboride nanopartieles, with high emission electrons in cathode materials and peculiar blocking near infrared wavelengths, were applied for many aspects. Based on the quasi-static approximation of Mie theory, the size dependent optical prop- erties of LaB6 nanoparticles were researched, such as refractive index n（ω）, extinction coefficient k（ω）, reflectivity R（ω）, absorption coefficient a（ω）, and electron energy loss L（ω）. Due to the localized surface plasmon resonance （LSPR）, the extinction coefficient k（ω） and absorption coefficient a（ω） depended on the size, and the LSPR peaks red-shifted with sizes increased, which was different from that of bulk materials. In addition, electron energy-loss spectrum L（co） showed electrons oscillation reinforced, since electrons absorbed the photon energy and generated resonance. Further, reftectivity R（ω） and refractive index n（ω） indicated that the light in near infrared region could not be propagated on the surface of LaB6 materials, which exhibited metallic behaviors. So the resonance peak of LaB6 nanoparticle was located in near-infrared region, making use of this property for solar control glazing and heat-shielding application.
基金In this research work,the Aeronautical Science Foundation of China(2018ZC63003)State Key Laboratory of Structural Analysis for Industrial Equipment(G19109,S18313)are gratefully acknowledged.
文摘In this paper,a local surface nanocrystallization technology is used for thin-walled structures with square cross sections,and an energy absorption device of two-staged combined energy absorption structure is proposed.In virtue of the surface nanocrystallization that enables to change the material on local positions,the structural deformation is induced and controlled to maximize the energy absorption capacity.A numerical model of the two-staged combined energy absorption structure is established,and the local surface nanocrystallization layout is optimized.The results show that the specific energy absorption of two-staged combined structure with local surface nanocrystallization can be increased by 34.36%compared with the untreated counterpart of the same material and structural shape.The ratio between the first and second peak crushing forces and the energy absorption allocation ratio between the two stages can be adjusted in the ranges of 0.26–0.55 and 0.31–0.45,respectively,which can be controlled by the local surface nanocrystallization designs.The numerical simulation and experimental results are in good agreement,which shows that the design for energy absorption device with local surface nanocrystallization is feasible and effective.
基金Funded by the National Natural Science Foundation of China(61366004)the Research Fund for the Doctoral Program of Higher Education(20123601110006)the Jiangxi Provincial Department of Education(KJLD13008)
文摘In order to enhance the p-type doping concentration in the LBSF, boron was added into the aluminum paste and boron doped local back surface field（B-LBSF） was successfully fabricated in this work. Through boron doping in the LBSF, much higher doping concentration was observed for the B-LBSF over the Al-LBSF. Higher doping concentration in the LBSF is expected to lead to better rear passivation and lower rear contact resistance. Based on one thousand pieces of solar cells for each type, it was found that the rear passivated crystalline silicon solar cells with B-LBSF showed statistical improvement in their photovoltaic properties over those with Al-LBSF.
基金supported by the National Key Research and Development Program of China under Grants No.2017YFA0701000,No.2018YFF01013001,and No.2020YFA0714001the Natural Science Foundation of China under Grants No.61988102,No.61921002,and No.62071108。
文摘The simulation mechanism of surface plasmon polaritons(SPPs)and localized surface plasmon(LSP)in different structures was studied,including the Au reflection grating(Au grating),Au substrate with dielectric ribbons grating(Au substrate grating),and pure electric conductor(PEC)substrate with Au ribbons grating(Au ribbons grating).And the characteristics of the Smith-Purcell radiation in these structures were presented.Simulation results show that SPPs are excited on the bottom surface of Au substrate grating grooves and LSP is stimulated on the upper surface both of Au ribbons grating grooves and Au grating grooves.Owing to the irreconcilable contradiction between optimizing the grating diffraction radiation efficiency and optimizing the SPPs excitation efficiency in the Au substrate grating,only 40-times enhancement of the radiation intensity was obtained by excited SPPs.However,the LSP enhanced structure overcomes the above problem and gains much better radiation enhancement ability,with about 200-times enhancement obtained in the Au ribbons grating and more than 500-times enhancement obtained in the Au grating.The results presented here provide a way of developing miniature,integratable,tunable,high-power-density radiation sources from visible light to ultraviolet rays at room temperature.
