A novel compact dual-band bandpass fllter using tri- section stepped impedance resonators (SIRs) is presented for Wireless Local Area Network (WLAN). SIRs and one stub between parallel couple line are employed to realize two satisfactory passbands. Meanwhile, transmission zero generated the passbands achieve a high out-of-band rejection. Simulated results show that central frequencies located at desired 2.4 5.2GHz with 3dB fractional bandwidths of 6.3% 3.4% respectively. The measured in good...

The dispersion characteristics of asymmetric double-negative material slab waveguides have been investigated by using normalized parameters. results show that the these differ dramatically from conventional guided waves, and they possess a number unusual properties, including absence fundamental modes, propagation first-order mode within narrow frequency ranges, existence modes for imaginary transverse wave numbers, example. In particular, one fast mode, near cutoff, corresponds to two...

A two-way Fano resonance switch in the plasmonic metamaterials has been proposed and experimentally demonstrated. The electrical is composed of two concentric spoof localized surface plasmons (LSPs) resonators. By adjusting slit inner LSPs resonator, different modes could be supported. loading a Schottky barrier diode (SBD) across both can simultaneously switched when SBD forward-biased or reverse-biased their status opposite. Both simulated measured results agree well at microwave...

Abstract A five narrow bands terahertz metamaterial absorber based on metal and Dirac semi-metal for high sensitivity refractive index sensing is designed in this paper. The a traditional sandwich structure. And the most remarkable difference that two hybrid materials (metal semi-metal) are used top layer. numerical results show absorption peaks can be achieved at 5.527, 5.759, 7.247, 9.257 10.186THz, among which perfect achieve 7.247 respectively. physical mechanism of proposed analyzed...

In this paper, we present two new photonic crystal structures, which are composed of fractal Cantor multilayer with defects embedded in its middle. Optical transmission matrix method is used to calculating the transmittance and reflectance. Compared general multilayer, find these structures have wider stopbands show super narrow bands middle stopbands. They can be served as bandpass filters. The pass band obtained less than 0.6nm near infrared 1530 nm when there a defect cantor multilayer....

With the advantages of high accuracy and fast response, piezoelectric actuators are used to drive optical image stabilizers. As a stack is not tensile, preload voltage required for traditional driven stabilizer, which wastes electricity adversely affects stack’s performance. In this paper, we propose double gimbal whereupon prototype machined its performance assessed. Two stacks produce forward reverse actuation, respectively, in case essential. Owing isolation gimbal, output coupling two...

In this paper, the formula of reflection coefficient multi-layer chiral media is derived by non-symmetric transmission-line method. Then, it applied to 1-D photonic crystal structure, which composed thin layers sandwiched air. The results show that difficult obtain band gap for general dielectric when difference two refractive indices isn't large, and small. With increasing index medium, becomes gradually bandwidth basically keeps unchanged. These characteristics are agreed with theoretical...

According to Maxwell equations and constitutive relations in chiral medium, the dispersion characteristic of symmetric slab waveguide with negative refractive medium is studied. The expressed normalized parameter are deduced waveguide. numerical results show that has great influence on When relative about 0.0477, zero order mode left-handed polarized wave disappears. While it greater than 1, core becomes In addition, compared general waveguide, tendency curves also analyzed.

The characteristics of a chiral negative refraction parallel-plate waveguide under PMC boundary are studied theoretically, and the corresponding dispersion relations, cut-off frequencies, propagating guided modes obtained. Some novel features found, such as fundamental mode will be not exist only if chirality parameter κ>1, in addition, cutoff frequency is no longer conventionally defined when propagation constant zero, but least that can still propagate. According to relations between β...

Characteristics of silica optical material largely depend on its thermal history. In this paper, formation thermally induced defects in is studied. The process defect analyzed detail. results show that there an obvious difference by heating treatment when the composition changes. Defect mainly displays as produce initial are zero. However, expresses and annealing not concentration can be decreased significantly heated high temperature. At same time, new also produced. These theoretic...

In this paper, defect induced by heated treatment in silica is studied. The formation process of analyzed the thermodynamic model. results show that can be produced thermal process. concentration affected many factors. related to initial precursors. To pure glass, precursors mainly come from strained bonds network. It produce centers and nonbridging oxygen hole (NBOHCs). These defects are also temperature conversion frequency between defects. changes with discussed detail.

In this paper, a novel chiral photonic crystal structure is presented. The formula of reflection coefficient multi-layer media applied to dielectric-chiral structure, which composed thin layers sandwiched by conventional media. To compare with previous literature, we consider the dielectric alternate glass and GaAs layers. power reflectance as function wavelength for has been calculated. results are in good agreement that Reference. However, our method simpler. From these graphs, it found...

In this paper, we present a novel cross section shape DCF. Truncated from circular DCF, the inner cladding of DCF is bounded by two equal angular spiral curves. By using concept mean transverse path between successive encounters core, developed new method to calculate absorption efficiency per unit fiber length. For with largest radius <i>R</i>=100<i>&#956;m</i> , doped core <i>r₀</i>=4<i>&#956;m</i> and angle parameter curve <i>&#952;</i>=0.04 calculated...