共查询到20条相似文献,搜索用时 15 毫秒
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设计了一种带有纳米天线的金属微腔结构, 以实现高强度表面等离子的定向激发. 在利用双狭缝结构实现表面等离子体波定向激发的基础上, 分别结合共振增强和干涉相长原理, 在传统结构的入射端面上添加纳米天线结构, 并增加狭缝通道数, 实现了定向激发的表面等离子体波的能量增强. 基于纳米天线的多通道高强度定向表面等离子体波激发装置结构简单, 系统紧凑, 并能够有效提高定向传播的表面等离子体波的能量密度和传播距离, 其对微纳光学传输和高密度光学集成领域等方面的研究具有重要意义. 相似文献
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V. V. Ivanov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2009,3(4):507-512
The technique of ultrahigh-resolution nonlinear fluorescent microscopy based on standing surface plasmons is proposed. On the wavelength of a surface plasmon of 20 nm the expected lateral resolution should be 1–2 nm. Slow surface plasmons with the required mean free path of ~1 m are possible in the planar amplifying medium-metal-dielectric structures due to the compensation of loss in the metal by the amplification in the active medium. In the optical and near infrared range the undamped surface plasmons with the wavelength of 20–50 nm in thin silver films can be obtained at the material gain of active medium of (1–2) × 104 cm ?1. Possibilities of obtaining this gain in the plasmon structures remain to be seen. 相似文献
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The specific features of elastic scattering of volume waves and surface plasmon polaritons by polycrystalline gold films have
been investigated. An analysis of the relative scattered energy, power spectral density of surface roughness, and integral
and angular dependences of scattering of waves of different nature indicates a strong nonradiative multiple scattering of
surface plasmon polaritons in gold films. When roughness increases, this scattering leads to an increase in scattering isotropy
and to a partial loss of structural information about gold films. The analysis of the scattered energy of surface plasmon
polaritons with application of the data on multifractal dimension of gold surface indicates also that the radiative scattering
of surface plasmon polaritons depends on both the rms surface roughness and the surface wave propagation length. 相似文献
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We present experimental results on ultralong-range surface plasmon polaritons, propagating in a thin metal film on a one-dimensional (1D) photonic crystal surface over a distance of several millimeters. This propagation length is about 2 orders of magnitude higher than the one in the ordinary Kretschmann configuration at the same optical frequency. We show that a long-range surface plasmon polaritons propagation may take place not only in a (quasi)symmetrical scheme, where a thin metal film is located between two media with (approximately) the same refraction index, but also in a scheme where the thin metal film is located between an appropriate 1D photonic crystal and an arbitrary (air, water, etc.) medium. The ultralong-range surface plasmon polaritons are potentially important for biosensors, plasmonics, and other applications. 相似文献
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Satoshi Ishii Alexander V. Kildishev Evgenii Narimanov Vladimir M. Shalaev Vladimir P. Drachev 《Laser \u0026amp; Photonics Reviews》2013,7(2):265-271
Inside of a hyperbolic medium, the principal components of the permittivity tensor have opposite signs causing the medium to exhibit a ‘metallicbr’ type of response to light wave sin one direction, and a ‘dielectric’ response in the other. Our study shows that inside hyperbolic media, volume plasmon polaritons (VPPs) propagate along the characteristic planes, forming distinct, directionally dependent optical responses. This is similar to the propagation of conventional surface plasmon polaritons (SPPs) along the planar interfaces separating the isotropic dielectrics and metallic slabs. Interestingly, the plasmon polariton propagates along the resonance cone in a volume of hyperbolic metamaterial crossing the interfaces of the constitutive materials. The Young's double‐slit scheme is used to study the spatially‐confined diffraction in a hyperbolic slab, made of many thin planar layers of a metal and dielectric, to obtain the sub‐wavelength interference pattern at the output interface. Proof‐of‐concept systems for producing such patterns applicable to nanolithography and subwavelength probes are demonstrated. 相似文献
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We report here experiments on surface plasmon excitation and propagation along corrugated and smooth aluminum surface in the terahertz frequency range. Narrowband plasmon excitation by a subpicosecond terahertz pulse is shown to be a transient process and plasmon propagation sufficiently changes its measured time profile. Plasmon propagation during its excitation and detection changes measured signal. We suggest to use parameters T (plasmon duration) and τ (plasmon lifetime) to describe the narrowband THz plasmon pulse. Plasmon duration and lifetime were defined and plasmon propagation lengths on smooth and corrugated surface were measured. Plasmon propagation length on flat surface turned out to be much smaller than it is predicted by the Drude model. 相似文献
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表面等离激元(surface plasmon polaritons, SPPs)控制具有重要意义.表面电磁波全息法是在金属表面设计能有效控制SPP传输的凹槽阵列结构.本文提出一种新的SPP传输的控制方法,利用金属-光折变材料复合全息结构控制SPP传播.在金属表面覆盖一层光折变材料,两束SPP波在光折变材料内干涉生成全息结构,利用此全息结构能够控制SPP的传播.通过时域有限差分法模拟验证,结果显示,通过金属-光折变材料复合全息结构可以有效地控制SPP波束的传输,实现SPP平面波束的单点聚焦、两点聚焦,以及生成零阶和一阶高斯SPP波束.经过优化发现,光折变材料的最佳厚度为3.3μm,最佳折射率调制度为0.06.现有SPP控制器件主要是通过离子束刻蚀,而金属-光折变材料复合全息结构不需要刻蚀,从而扩展了SPP控制的器件的制作方法,为SPPs的全光控制提供了新的思路,使SPP全光控制成为可能,进一步实现了SPP全光开关等功能. 相似文献
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金属纳米结构的表面等离激元可以突破光学衍射极限,为光子器件的微型化和集成光学芯片的实现奠定基础.基于表面等离激元的各种基本光学元件已经研制出来.然而,由于金属结构的固有欧姆损耗以及向衬底的辐射损耗等,表面等离激元的传输能量损耗较大,极大地制约了其在纳米光子器件和回路中的应用.研究能量损耗的影响因素以及如何有效降低能量损耗对未来光子器件的实际应用具有重要意义.本文从纳米线表面等离激元的基本模式出发,介绍了它在不同条件下的场分布和传输特性,在此基础上着重讨论纳米线表面等离激元传输损耗的影响因素和测量方法以及目前常用的降低传输损耗的思路.最后给出总结以及如何进一步降低能量损耗方法的展望.表面等离激元能量损耗的相关研究对于纳米光子器件的设计和集成光子回路的构建有着重要作用. 相似文献
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光刻技术(lithography)是微纳结构制备的关键技术之一.受限于光的衍射极限,传统光刻方法进一步缩小特征尺寸变得越来越难.表面等离子激元(surface plasmon polariton,SPP)作为光与金属表面自由电子密度振荡相互耦合形成的一种特殊电磁形式,具有波长短、场密度大、异常色散等特点,在突破传统光学衍射极限的研究和应用中具有重要的学术和实用价值.本文针对SPP在光刻胶中的非线性吸收及其在大视场纳米光刻中的应用进行了理论和实验探索.在回顾SPP概念的基础上,阐述了双SPP吸收的概念及其应用于纳米光刻的优势,明确了该效应具有与传统双光子吸收不同的内涵和特性.在800和400nm飞秒激光的作用下,实现了基于双SPP吸收效应的周期干涉条纹,同时验证了双SPP吸收的闽值效应,通过控制曝光计量实现了图形线宽的调控,最小线宽小于真空光波长的1/10.利用SPP波长短、场增强的特点,并结合非线性吸收的闽值效应,单次曝光区域比纳米图形尺度大4 5个数量级,曝光区域的直径可达1.6 mm.同时制备出较为复杂的同心圆环结构.基于双SPP吸收独有的特性以及SPP丰富的模式,有望进一步在大光刻视场、超小尺度图形光刻技术上获得突破. 相似文献
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The angular distribution of fluorescence emission from dye molecules excited by surface plasmon waves in a silver film is reported. Coupling of the emitted fluorescence to a surface plasmon mode at the Stokes shifted wavelength results in a sharply peaked angular profile in the prism half space. Fresnel theory is used to model experimental results obtained for thick and thin sample dye films and for micron-size particles containing dye. 相似文献
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A new concept of surface plasmon resonance fiber optic sensor is presented. By tuning the plasmon resonance to a wavelength for which the outer medium is absorptive, a significant variation of the spectral transmittance of the device is produced as a function of the concentration of the analyte. With this mechanism, selectivity can be achieved without the need of any functionalization of the surfaces or the use of recognizing elements, which is a very interesting feature for any kind of chemical sensor or biosensor. Doubly deposited uniform-waist tapered fibers are well suited for the development of these new sensors. Multiple surface plasmon resonance, obtainable in those structures, can be used for the development of microspectrometers based on this principle. 相似文献
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Alexander V. Korovin 《Optics Communications》2012,285(24):5191-5197
The essential increase of propagation length of a long range surface plasmon polariton in a thin symmetrically corrugated plasmon-carrying film embedded in a dielectric medium is theoretically predicted. The calculations are based on the differential formalism for the system of Maxwells equations where the solution for electromagnetic fields is written as a superposition of partial plane waves in the presentation of a curvilinear non-orthogonal coordinates system for simplifying the boundary conditions. The spectral and angular dependencies of p-polarized light transmittance/reflectance demonstrate that the in-plane shift between both profiles of corrugated film drastically changes the surface plasmon polariton propagation length from minimum of the asymmetric profile to maximum of the symmetric one. The obtained results were qualitatively explained using the model of weakly coupled photonic wells. 相似文献
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The field distribution of the surface plasmon (SP) around a silver nanowire greatly influences its applications for both spectrum enhancement and nano-waveguide. This paper demonstrates the change of the SP local field distribution of a silver nanowire on glass substrate with the refractive index of the covering medium by numerical simulation. The hot energy site is observed focusing on the interface between the nanowire and the surround material of larger refractive index. Moreover, we also find that the surface plasmon field becomes more confined as the refractive index between the substrate and medium has a larger gap, while a homogeneous distribution of the surrounding dielectric material around the nanowire shows a uniform local field distribution with a larger surface plasmon propagation length. The change of related parameters, such as effective index, mode area, and propagation length are also comprehensively investigated against the refractive index for nanowires with 100, 200, 300 nm diameter. Considering the wide use of polymethyl methacrylate (PMMA) material, the field distribution of silver nanowire partially imbedded in PMMA against the PMMA thickness is also studied. 相似文献
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Tapered dielectric structure in metal as a wavelength-selective surface plasmon polariton focuser 下载免费PDF全文
Symmetric tapered dielectric structures in metal have
demonstrated applications such as the nanofocusing of surface
plasmon polaritons, as well as the waveguiding of V-channel
polaritons. Yet the fabrication of smooth-surfaced tapered structure
remains an obstacle to most researchers. We have successfully
developed a handy method to fabricate metal-sandwiched tapered
nanostructures simply with electron beam lithography. Though these
structures are slightly different from conventional symmetric
V-shaped structures, systematic simulations show that similar
functionality of surface plasmon polariton nanofocusing can still be
achieved. When parameters are properly selected,
wavelength-selective nanofocusing of surface plasmon polaritons can
be obtained. 相似文献
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Gubin M. Yu. Dzedolik I. V. Prokhorova T. V. Pereskokov V. S. Leksin A. Yu. 《Optics and Spectroscopy》2022,130(5):303-309
Optics and Spectroscopy - Specific features of optical control of propagation of surface plasmon polaritons in plasmonic circuits based on thin metal waveguides and semiconductor nanostructures are... 相似文献
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Gain-assisted propagation of electromagnetic energy in subwavelength surface plasmon polariton gap waveguides 总被引:1,自引:0,他引:1
Stefan A Maier 《Optics Communications》2006,258(2):295-299
The propagation of electromagnetic energy via coupled surface plasmon polariton modes in a metal-insulator-metal heterostructure is analyzed analytically for a core material exhibiting optical gain. It is shown that a sufficiently large gain can completely compensate for the absorption losses due to energy dissipation in the metallic boundaries, enabling long-range transport with a confinement below the diffraction limit for on-chip switching and sensing applications. For a free-space wavelength of 1500 nm, lossless propagation in a gold-semiconductor-gold waveguide with a core size of 50 nm is predicted for a gain coefficient γ = 4830 cm−1, comparable to that of semiconductor gain media. The gain requirements decrease with the use of low-index nanocrystal-doped glasses or polymers as core materials. 相似文献