共查询到18条相似文献,搜索用时 62 毫秒
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金属薄膜上制备的表面等离激元颜色滤波器具有很强的颜色可调性. 在200 nm厚的金膜上, 通过聚焦离子束刻蚀, 制备一系列周期逐渐变化的圆形、方形、矩形亚波长尺寸小孔方阵列表面等离激元颜色滤波器, 改变入射光的偏振方向, 观察其超透射滤波现象. 研究发现: 对于矩形小孔阵列, 其透射光颜色随入射光偏振方向的变化而改变; 而对于圆形、方形的小孔阵列, 其透射光颜色对入射光的偏振方向并不敏感. 分析表明, 对于金膜上刻蚀的小孔结构, 虽然结构的周期性导致的表面等离激元极化子会对透射光的颜色变化产生一定影响, 但是随小孔形状变化的局域表面等离激元共振才是影响透射光颜色的决定性因素. 如果入射光没有在小孔中激发出局域表面等离激元, 则表面等离激元极化子对透射光的影响也会消失. 根据不同形状小孔周期结构透射光颜色随入射光的偏振变化特点, 制备出了包含两种小孔形状的复合周期结构. 随着入射光偏振方向的改变, 该结构会显示出不同的颜色图案.
关键词:
表面等离激元极化子
局域表面等离激元
颜色滤波器
亚波长小孔阵列 相似文献
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近年来,表面等离激元学(plasmonics)已经形成一个新的学科热点.电子在金属与介质界面的集体振荡行为形成一种元激发——表面等离激元(surface plasomon polariton,SPP).由于其具有特殊的耦合与传播性质,与SPP相关的器件设计与应用成为目前纳米光子学领域的国际前沿研究方向.文章介绍了利用微纳加工技术制备的SPP纳米结构,以及利用近场光学表征手段对SPP聚焦、波导、共振增强现象研究的进展. 相似文献
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表面等离激元的聚焦与波导增强 总被引:1,自引:0,他引:1
近年来,表面等离激元学(plasmonics)已经形成一个新的学科热点.电子在金属与介质界面的集体振荡行为形成一种元激发——表面等离激元(surface plasomon polariton,SPP).由于其具有特殊的耦合与传播性质,与SPP相关的器件设计与应用成为目前纳米光子学领域的国际前沿研究方向.文章介绍了利用微... 相似文献
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《Photonics and Nanostructures》2014,12(5):508-514
Transmission properties of plasmonic structure arrays are simulated by finite element method. The array unit is composed of two combined triangular prisms. Results reveal that several resonant modes are found in the transmission spectra, which are due to the resonance of the surface plasmon polariton in the metal slit or to the localized surface plasmon resonance of the combined prisms. The resonant wavelengths can be tuned by changing the structural parameters of the combined prisms. In addition, the resonant modes are sensitive to small refractive index changes of the surrounding media, revealing potential detection applications in nanophotonic systems. 相似文献
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《Current Applied Physics》2018,18(11):1381-1387
One dimensional (1D) grating has been fabricated (using focused ion beam) on 50 nm gold (Au) film deposited on higher refractive index Gallium phosphate (GaP) substrate. The sub-wavelength periodic metal nano structuring enable to couple photon to couple with the surface plasmons (SPs) excited by them. These grating devices provide the efficient control on the SPs which propagate on the interface of noble metal and dielectric whose frequency is dependent on the bulk electron plasma frequency of the metal. For a fixed periodicity (Λ = 700 nm) and slit width (w = 100 nm) in the grating device, the efficiency of SPP excitation is about 40% compared to the transmission in the near-field. Efficient coupling of SPs with photon in dielectric provide field localisation on sub-wavelength scale which is needed in Heat Assisted Magnetic recording (HAMR) systems. The GaP is also used to emulate Vertical Cavity Surface emitting laser (VCSEL) in order to provide cheaper alternative of light source being used in HAMR technology. In order to understand the underlying physics, far-and near-field results has been compared with the modelling results which are obtained using COMSOL RF module.Apart from this, grating devices of smaller periodicity (Λ = 280 nm) and slit width (w = 22 nm) has been fabricated on GaP substrate which is photoluminescence material to observe amplified spontaneous emission of the SPs at wavelength of 805 nm when the grating device was excited with 532 nm laser light. This observation is unique and can have direct application in light emitting diodes (LEDs). 相似文献
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Pierre Berini 《Laser \u0026amp; Photonics Reviews》2014,8(2):197-220
Surface plasmon photodetectors are of vigorous current interest. Such detectors typically combine a metallic structure that supports surface plasmons with a photodetection structure based on internal photoemission or electron‐hole pair creation. Detector architectures are highly varied, involving surface plasmons on planar metal waveguides, on metal gratings, on nano‐particles, ‐islands, or ‐antennas, or involving plasmon‐mediated transmission through one or many sub‐wavelength holes in a metal film. Properties inherent to surface plasmons, such as sub‐wavelength confinement and their ability to resonate on tiny metallic structures, are exploited to convey useful characteristics to detectors in addressing applications such as low‐noise high‐speed detection, single‐plasmon detection, near‐ and mid‐infrared imaging, photovoltaic solar energy conversion, and (bio)chemical sensing. The operating principles behind surface plasmon detectors are reviewed, the literature on the topic is surveyed, and avenues that appear promising are highlighted. 相似文献
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Influence of polarization direction, incidence angle, and geometry on near-field enhancement in two-layered gold nanowires 下载免费PDF全文
The influences of polarization direction, incidence angle, and geometry on near-field enhancements in two-layered gold nanowires (TGNWs) have been investigated by using the vector wave function method. When the polarization direction is perpendicular to the incidence plane, the local field factor (LFF) in TGNW decreases first and then increases with the increase in the incidence angle. The minimum LFF is observed at an incidence angle of 41°. It is found that the increase in the dielectric constant of the inner core leads to a decrease in the LFF. With the increase in the inner core radius, the LFF in TGNW increases first and then decreases, and the maximum LFF is observed at an inner core radius of 27 nm. On the other hand, when the polarization direction is parallel to the incidence plane, the collective motions of the induced electrons are enhanced gradually with the decrease in the incidence angle, and hence the near-field enhancement is increased. 相似文献
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Surface plasmon polaritons frequency-blue shift in low confinement factor excitation region 下载免费PDF全文
Ling-Xi Hu 《中国物理 B》2021,30(8):84102-084102
Surface plasmon polaritons' (SPPs') frequency blue shift is observed in finite-difference time-domain (FDTD) simulation of parallel electron excitation Au bulk structure. Comparing with cold dispersion of SPPs, an obvious frequency blue shift is obtained in low confinement region excitation simulation results. Then, according to SPPs' transverse attenuation characteristics, the excited frequency mode instead of cold dispersion corresponding frequency mode matches it. Thence, this excited mode is confirmed to be SPPs' mode. As is well known the lower the frequency, the smaller the confinement factor is and the lower the excitation efficiency, the wider the bandwidth of excited SPPs is. And considering the attenuation in whole structure, the excited surface field contains attenuation signal. In a low confinement factor region, the higher the SPPs' frequency, the higher the excitation efficiency is, while broadband frequency information obtained in attenuation signal provides high frequency information in stimulation signal. Thence, in the beam-wave interaction, as the signal oscillation time increases, the frequency of the oscillation field gradually increases. Thus, compared with cold dispersion, the frequency of excited SPP is blueshifted This hypothesis is verified by monitoring the time domain signal of excited field in low and high confinement factor regions and comparing them. Then, this frequency-blue shift is confirmed to have commonality of SPPs, which is independent of SPPs' material and structure. Finally, this frequency-blue shift is confirmed in an attenuated total reflection (ATR) experiment. Owing to frequency dependence of most of SPPs' devices, such as coherent enhancement radiation and enhancement transmission devices, the frequency-blue shift presented here is of great influence in the SPPs applications. 相似文献
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Lina Wang Likang Cai Jing Zhang Wenli Bai Haifeng Hu Guofeng Song 《Journal of Raman spectroscopy : JRS》2011,42(6):1263-1266
A metallic bowtie nanoring array is designed to gain high sensitive and reproducible substrate for surface‐enhanced Raman scattering (SERS) spectroscopy. The localized surface plasmon resonance (LSPR), the electric field enhancement factors (EFs) and the electric field distribution of the bowtie and bowtie nanoring array are numerically investigated by means of the finite‐difference time domain (FDTD) method. After the optimization of the particle size and the array period, the maximum electromagnetic field EF approaches 153, and the corresponding SERS electromagnetic enhancement factor (EMEF) reaches 5.4 × 108. This highly sensitive and reproducible substrate can be a good candidate for SERS applications. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Noble metallic nanostructures exhibit special optical properties resulting from excitation of surface plasmons. Among the various metallic nanostructures, nanorods have attracted particular attention because of their unique and intriguing shape-dependent plasmonic properties. Nanorods can support transverse and longitudinal plasmon modes, the latter ones depending strongly on the aspect ratio of the nanorod. These modes can be routinely tuned from the visible to the near-infrared spectral regions. Although nanorods have been investigated extensively, there are few studies devoted to nanostructures deviating from the nanorod shape. This review provides an overview of recent progress in the development of two kinds of novel quasi-one-dimensional silver nanostructures, nanorice and nanocarrot, including their syntheses, crystalline characterizations, plasmonic property analyses, and performance in plasmonic sensing applications. 相似文献
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Hui Feng Ma Xiaopeng Shen Qiang Cheng Wei Xiang Jiang Tie Jun Cui 《Laser \u0026amp; Photonics Reviews》2014,8(1):146-151
The conversion from spatial propagating waves to surface plasmon polaritons (SPPs) has been well studied, and shown to be very efficient by using gradient‐index metasurfaces. However, feeding energies into and extracting signals from functional plasmonic devices or circuits through transmission lines require the efficient conversion between SPPs and guided waves, which has not been reported, to the best of our knowledge. In this paper, a smooth bridge between the conventional coplanar waveguide (CPW) with 50 Ω impedance and plasmonic waveguide (e.g., an ultrathin corrugated metallic strip) has been proposed in the microwave frequency, which converts the guided waves to spoof SPPs with high efficiency in broadband. A matching transition has been proposed and designed, which is constructed by gradient corrugations and flaring ground, to match both the momentum and impedance of CPW and the plasmonic waveguide. Simulated and measured results on the transmission coefficients and near‐filed distributions show excellent transmission efficiency from CPW to a plasmonic waveguide to CPW in a wide frequency band. The high‐efficiency and broadband conversion between SPPs and guided waves opens up a new avenue for advanced conventional plasmonic integrated functional devices and circuits. 相似文献