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611.
The multipolar spoof localized surface plasmons (LSPs) on a planar textured metallic disk are proposed and experimentally demonstrated at microwave frequencies. Based on ultrathin metal film printed on a thin dielectric substrate, the designed plasmonic metamaterial clearly shows multipolar plasmonic resonances, including the dipole, quadrupole, hexapole, octopole, decapole, dodecapole, and quattuordecpole modes. Both numerical simulations and experiments are in good agreement. It is shown that the spoof LSP resonances are sensitive to the disk's geometry and local dielectric environments. Hence, the ultrathin textured metallic disk may be used as plasmonic sensors and find potential applications in the microwave and terahertz frequencies. 相似文献
612.
We propose and analyze the finite volume method for solving the variational inequalities of first and second kinds. The stability and convergence analysis are given for this method. For the elliptic obstacle problem, we derive the optimal error estimate in the H1‐norm. For the simplified friction problem, we establish an abstract H1‐error estimate, which implies the convergence if the exact solution u∈H1(Ω) and the optimal error estimate if u∈H1 + α(Ω),0 < α≤2. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
613.
研究了不同沟道厚度的In0.53Ga0.47As/In0.52Al0.48As量子阱中双子带占据的二维电子气的输运特性.在考虑了两个子带电子之间的磁致子带间散射效应后,通过分析Shubnikov-de Haas振荡一阶微分的快速傅里叶变换结果,获得了每个子带电子的浓度、输运散射时间、量子散射时间以及子带之间的散射时间.结果表明,对于所研究的样品,第一子带电子受到的小角散射更强,这与第一子带电子受到了更强的电离杂质散射有
关键词:
二维电子气
散射时间
自洽计算 相似文献
614.
在低温强磁场条件下,对In0.53Ga0.47As/In0.52Al0.48As量子阱中的二维电子气进行了磁输运测试.在低磁场范围内观察到正磁电阻效应,在高磁场下这一正磁电阻趋于饱和,分析表明这一现象与二维电子气中的电子占据两个子带有关.在考虑了两个子带之间的散射效应后,通过分析低磁场下的正磁电阻,得到了每个子带电子的迁移率,结果表明第二子带电子的迁移率高于第一子带电子的迁移率.进一步分析表明,这主要是由两个子带之间的
关键词:
二维电子气
正磁电阻
子带散射 相似文献
615.
Silveirinha and Engheta have recently proposed that electromagnetic waves can tunnel through a material with an electric permittivity (epsilon) near zero (ENZ). An ENZ material of arbitrary geometry can thus serve as a perfect coupler between incoming and outgoing waveguides with identical cross-sectional area, so long as one dimension of the ENZ is electrically small. In this Letter we present an experimental demonstration of microwave tunneling between two planar waveguides separated by a thin ENZ channel. The ENZ channel consists of a planar waveguide in which complementary split ring resonators are patterned on the lower surface. A tunneling passband is found in transmission measurements, while a two-dimensional spatial map of the electric field distribution reveals a uniform phase variation across the channel--both measurements in agreement with theory and numerical simulations. 相似文献
616.
Xiaojia Tang Lin Guo Quan Liu Yeye Li Tie Li Yimin Zhu 《Crystal Research and Technology》2015,50(3):203-209
In order to investigate the microstructure of magnesium oxide hydration product within seawater, two reaction conditions (liquid‐solid and gas‐liquid‐solid) and two solutions (seawater and deionized water) were adopted for magnesium oxide hydration. The characterization of the hydration product using X‐Ray diffraction and scanning electron microscope was performed. Experimental results indicate that cations and anions in seawater promote the hydration. Most of the hydration products within seawater system display flower‐like morphology, but the agglomeration phenomenon is not obvious within deionized water system, especially for the supernatant layer products within deionized water system under gas‐liquid‐solid reaction condition. There was no stratification phenomenon occurred when MgO hydrated with seawater under three‐phase reaction condition. 相似文献
617.