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1.
The arbitrarily open trapezoidal-groove guide is analyzed with the conformal mapping technique. A new formula is given for
the evaluation of one fundamental parameter associated with the technique. The relationship between the cut-off wavelength
for the dominant mode and the geometry of the guide structure is studied; dispersion characteristic of the groove guide is
also given. Some numerical results are shown to be in good agreement with both experimental data and the results of the finite
element method (FEM). Moreover, it is testified that dispersion of the trapezoidal-groove guide is low. The obtained results
are significant for the design and application of the open trapezoidal-groove guide for millimeter waves. 相似文献
2.
Fuyong Xu Keyu Zhao Xuenong Tian 《International Journal of Infrared and Millimeter Waves》2000,21(7):1119-1129
The transmission characteristics of the mode TE11 for a new type of closed trapezoidal-groove guide with arbitrary inclined angle are analysed in detail with the mode-matching method in this paper. The calculated results are in good agreement with the experimental values in the published reference. The dispersion of the closed trapezoidal-groove guide is very low. The relationships of the cut-off wavelength and the attenuation constant with the structural sizes of the closed trapezoidal-groove waveguide are also obtained. The given results have very important value in study, design, manufacture and application for closed trapezoidal-groove waveguide. 相似文献
3.
Fuyong Xu Keyu Zhao Mai Lu 《International Journal of Infrared and Millimeter Waves》1996,17(2):403-413
In this paper, the dispersion characteristics of the main mode for the trapezoidal-groove guides are analysed by using the approach of equivalent network with transverse resonance. The relationship curves between guide wavelength, phase constant and guide dimensions, frequency are obtained. The characteristics have important values in design, manufacture and application of groove guides. 相似文献
4.
Fuyong Xu Keyu Zhao Bin You Xiaohui Lin 《International Journal of Infrared and Millimeter Waves》1999,20(10):1825-1835
In this paper, the dispersion, cut-off and attenuation characteristics of trapezoidal-groove guide are analyzed by using the mode-matching method. The relationships between the guided parameters and variations of relative guide's sizes are discussed in detail. The calculated results are in good agreement with those in relevant reference. So, the obtained conclusions have important values in theoretical studies and actual applications of trapezoidal-groove guides for millimeter and submillimeter waves. 相似文献
5.
Mai Lu Fulin Wei Zhuoxiang Ren Zheng Yang 《International Journal of Infrared and Millimeter Waves》1999,20(4):645-654
The structure of closed trapezoidal-groove guide is similiar to that of open one, but it can be used to prevent energy from leaking out of the guide. In this paper, the propagation characteristics of dominant mode in closed trapezoidal-groove guide are analysed by using finite element method and the results are discussed. 相似文献
6.
Fuyong Xu Bin You Yue-e Li Keyu Zhao 《International Journal of Infrared and Millimeter Waves》2002,23(10):1545-1556
The modes TE and TM of arbitrarily trapezoidal-groove guide are analyzed by using the mode-matching method. The mode TE11 is the dominant mode of the trapezoidal-groove guide under different conditions. The bandwidth characteristic and the operation condition for the single dominant mode are discussed. The obtained conclusions are of very important significance in theoretical study and practical application of trapeziodal-groove guides for millimeter waves. 相似文献
7.
Analysis for Transmission Characteristics of Closed Trapezoidal-Groove Waveguide with Boundary Element Method 总被引:1,自引:0,他引:1
Fuyong Xu Xiaohui Lin Bin You 《International Journal of Infrared and Millimeter Waves》1999,20(9):1691-1699
In this paper, the cut-off and dispersion characteristics of a new kind of closed trapezoidal-groove waveguide that has more advantages than open groove waveguides are analyzed with the help of the boundary element method, the relationship between cut-off wavelengths and variations of guide's relative sizes is discussed in detail. The calculated results are in good agreement with those in the relevant reference. So, the obtained conclusions are very important in theoretical studies and actual applications of closed trapezoidal-groove waveguides for millimeter and submillimeter waves. 相似文献
8.
Fuyong Xu Keyu Zhao Bin You Xiaohui Lin 《International Journal of Infrared and Millimeter Waves》2000,21(1):45-56
In this paper, the transmission properties such as the dispersion and attenuation characteristics for the dominant mode of the trapezoidal-groove waveguide with arbitrarily inclined angle are analyzed and discussed by using the mode-matching method. Some calculated results are in very good agreement with the published data. The obtained conclusions are of important significance in theoretical studies and actual applications of trapezoidal-groove waveguides for millimeter and submillimeter waves. 相似文献
9.
Godfrey Brendan B. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1978,6(4):380-383
We investigate the dispersion relation for long wavelength slow Langmuir waves in a relativistic particle beam propagating along a strong magnetic guide field in an evacuated metallic waveguide. For a large class of beam radial profiles, wave phase velocity drops to zero with infinite slope as beam current approaches the space-charge limit. This result is of importance to certain collective ion acceleration proposals. 相似文献
10.
Shen Zhongxiang Hua Rongxi 《International Journal of Infrared and Millimeter Waves》1991,12(4):389-396
An improved solution to the dominant mode properties of groove guides of general cross section is presented in this paper. A novel differential equation is formulated and solved by numerical integration technique. Numerical results for single V-groove guide show good agreement with available measured values. Calculated results for the cutoff wavelengths of semicircular-groove and trapezoidal-groove guides are presented. 相似文献
11.
12.
We propose a novel method to achieve highly nonlinear photonic crystal fiber (PCF) by filling highly nonlinear liquid chloroform in the core of hollow-core PCF (HCPCF). The dispersion properties and electric field distribution of the fundamental mode are calculated by using the full-vector finite element method (FVFEM). Simulation results indicate that the zero-dispersion wavelength (ZDWL) of the chloroform-filled PCF is adjustable around 800 nm. Hence the femtosecond laser pulses with central wavelength at 800 nm can propagate in anomalous dispersion regime of the PCF, inducing the spectra broadening. 相似文献
13.
I. P. Christov 《Applied physics. B, Lasers and optics》2005,80(4-5):405-408
The guiding of an attosecond (as) X-ray pulse in a two-dimensional atomic structure is analyzed. The results obtained from a simple model show that an atomic-scale waveguide which consists of a barium monoxide lattice where five rows of atoms have been removed can successfully guide pulses with duration 20 as and wavelength 10 Å. This is attributed to an improved total external reflection in the discrete atomic structure. When the carrier frequency is higher than the plasma frequency, the guide causes minor distortions in the pulse profile. For lower frequencies, the X-ray pulse is significantly affected by the guide dispersion. These results indicate that nano- and sub-nanostructures can be designed for transportation and processing of coherent attosecond-duration electromagnetic pulses, which is important for the newly emerging field of X-ray photonics. 相似文献
14.
Dominant mode characteristics of circular groove guide 总被引:1,自引:0,他引:1
Hu Chi Yang Hong-sheng Lu Zhong-zuo 《International Journal of Infrared and Millimeter Waves》1995,16(2):401-410
Circular groove guide is a kind of waveguide for millimeter waves with low loss, large dimensions, and low dispersion. In this paper, the dominant mode characteristics of it is analysed. The technique that mode macthing method combines with point matching method is used to derive the Nth-order characteristic equation of the guide. The 1st order, 2nd order and 3rd order approximate curves that the normalized cutoff wavelength of circular groove guide varies with c/a are given. The attenuation curves are given at 1mm, 1.5mm and 3mm wavelength. The numerical results are in well agreement with the experimental results published.Supported by National Science Foundation of P. R. China 相似文献
15.
凹形色散分布光纤中超连续谱特性分析 总被引:5,自引:0,他引:5
比较了在不同色散分布的色散渐减光纤中超连续(SC)谱的产生。结果表明,当光纤的色散值关于中心波长对称、且随着传输距离增加,经由反常色散区过渡到正常色散区的、凹形色散分布的色散渐减光纤更有利于产生平坦、带宽的超连续谱。从频域的全场方程出发,模拟了脉冲在光纤中的传输情形,发现脉冲在凹形色散分布的光纤中传输时,不仅在反常色散区能更大程度被压缩,在正常色散区由于存在零色散波长点,还能更进一步展宽,从而得到更宽、更平坦的超连续谱。在谱强为-27dB时,谱宽可达到298nm,比相同情况下的凸形色散的光纤中超连续谱增宽97nm。结果显示,凹形色散分布的光纤比凸形色散分布的光纤在超连续谱的产生上有更明显的优势,可以得到更宽的超连续谱。 相似文献
16.
In this paper,we introduce a horizontal slot in the reversed-rib chalcogenide glass waveguide to tailor its dispersion characteristics.The waveguide exhibits a flat and low dispersion over a wavelength range of 1080 nm,in which the dispersion fluctuates between-10.6 ps·nm~(-1)·km~(-1) and +11.14 ps·nm~(-1)·km~(-1).The dispersion tailoring effect is due to the mode field transfer from the reversed-rib waveguide to the slot with the increase of wavelength,which results in the extension of the low dispersion band.Moreover,the nonlinear coefficient and the phase-matching condition of the fourwave mixing process in this waveguide are studied,showing that the waveguide has great potential in nonlinear optical applications over a wide wavelength range. 相似文献
17.
We consider wave propagation in a model of a deep ocean acoustic wave guide with a periodic range dependence. It is assumed that the wave field is governed by the parabolic equation. Formally the mathematical model of the wave guide coincides with that of a quantum system with time-dependent Hamiltonian. From the analysis of Floquet modes of the wave guide it is shown that there exists a "scarring" effect similar to that observed in quantum systems. It turns out that the segments of an unstable periodic ray trajectory may be distinguished in the spatial distribution of the wave field intensity at a finite wavelength. Besides the scarring effect, it is found that the so-called "stable islands" in the phase space of ray dynamics reveal themselves in the coarse-grained Wigner functions of the Floquet modes. 相似文献
18.
单模光纤中偏振模色散的仿真模型 总被引:3,自引:3,他引:0
利用琼斯矩阵法研究了长单模光纤中偏振模色散的仿真模型.考虑到偏振模色散的随机性,该模型中单模光纤被看作是一系列短双折射光纤段的级联,相邻两段之间耦合角是随机的.研究结果表明,当短双折射光纤段等长时,偏振模色散呈现随波长周期性变化的特点;不符合实际情况.当短双折射光纤段不等长且服从高斯分布时,周期性逐渐消失;当其长度均方差为均值的20%,周期性完全消失.最后比较了偏振模色散的时域统计特性.取短双折射光纤段的长度服从高斯分布且均方差为均值的20%,偏振模色散的统计特性接近于实际分布.因此得出结论:为了正确估计偏振模色散的影响,在单模光纤的级联模型中,短双折射光纤段的长度应服从高斯分布,均方差为其均值的20%. 相似文献
19.