共查询到20条相似文献,搜索用时 15 毫秒
1.
A novel network approach is proposed to analyze periodic dielectric waveguide of finite length. Our approximate analysis is
to consider a bounded waveguide problem in which perfectly-conducting walls are introduced, and the periodic corrugation is
regarded as consisting of step discontinuities connected by a length of uniform slab waveguide. Application of conservation
of complex power technique (CCPT) allows us to take into account of both surface modes and only a few non-surface-modes, and
readily derive propagation characteristics of the wave-guide with finite periodic corrugations around Bragg interaction region. 相似文献
2.
Guidance of Surface Waves with Dielectric Waveguides Having Finite or Infinite Periodic Corrugations
Liu Huikan Dong Tianlin 《International Journal of Infrared and Millimeter Waves》2005,26(10):1389-1406
A planar open dielectric waveguide with periodic rectangular corrugations is investigated in the case that surface wave is
guided and propagates normally to the corrugation. Our approximate analysis with the propagation characteristics is to consider
a corresponding bounded waveguide problem in which perfect electric or magnetic walls are introduced, and the periodic corrugation
is regarded as consisting of step discontinuities connected by a length of uniform slab waveguide. By properly taking into
account of both surface modes and only a few non-surface-modes, and using conservation of complex power technique (CCPT) as
well as solution selection rule (SSR), we can readily derive propagation characteristics in the Bragg interaction region.
The calculated results show an excellent agreement with previously published ones. 相似文献
3.
Keqian Zhang Jianguo Xiao Lian Gong 《International Journal of Infrared and Millimeter Waves》1998,19(9):1285-1291
The propagation characteristics of a planar waveguide with mirror-conjugate chiralities filled in the core and the cladding (mirror-conjugate chirality waveguide) are presented. The effects of chirality on cutoff, dispersion and field distribution characteristics of the waveguide are studied. The results show that the waveguide with desired features can be made by appropriately selecting the chiralities of the core and the cladding, because the core chirality and cladding chirality have different influences on waveguide propagation characteristics. 相似文献
4.
Keqian Zhang Jianguo Xiao Lian Gong 《International Journal of Infrared and Millimeter Waves》1998,19(9):1275-1284
The propagation characteristics of a planar waveguide with chiral media filled in the cladding are presented. The effect of chirality on cutoff, dispersion and field distribution of the waveguide are studied. The results show that the cladding chirality may lead to a single-mode operation in the planar waveguide. 相似文献
5.
Haixin Zhou Keqian Zhang Jianguo Xiao 《International Journal of Infrared and Millimeter Waves》1999,20(8):1549-1562
Eigenequations for a metal-coated planar chiral dielectric waveguide and a mirror-conjugate planar chiral dielectric waveguide are derived. The eigenequations are given in simple formulations. The results indicate that the perfect conductive (or magnetic) boundary can produce mirror-conjugate of chiral media and the left-handed and right-handed circularly polarized modes couple with each other due to the conductive boundary. The propagation characteristics of a metal-coated planar waveguide with chiral core are presented. An interesting phenomenon is observed that the field distributions vary with respect to the operating wavelength. 相似文献
6.
Haixin Zhou Keqian Zhang 《International Journal of Infrared and Millimeter Waves》1999,20(11):1977-1987
The propagation characteristics of a metal-coated planar waveguide with chiral media filled in the cladding are presented. The effects of chirality on cutoff, dispersion characteristics and field distributions of the waveguide are studied. The results show that cladding chirality brings phase chopping to the transverse electric field component of those modes with odd mode numbers. 相似文献
7.
Haixin Zhou Keqian Zhang 《International Journal of Infrared and Millimeter Waves》1999,20(11):1989-1999
The propagation characteristics of a circular dielectric waveguide with chiral media filled in the cladding are investigated. The relation between the cutoff frequency and the chiral admittance, the dispersion curves for some modes with different angular mode numbers and the transverse distribution of fields are presented. Some new features different from the ordinary circular dielectric waveguide are resulted. The results show that the cladding chirality may lead to a single-mode operation in the circular dielectric waveguide. 相似文献
8.
The method of designing a corrugated optical waveguide filter is proposed to yield an arbitrary spectral profile of the reflection coefficient. It gives the functional dependence of the corrugation depth on distance along the wave propagation direction. The basis of the theory of the method is a combination of the effective index approach and the Fourier transformation technique. It represents the spectral profile of the reflection coefficient approximately to Fourier transformation of the spatial profile of the effective refractive index. Examples are presented to illustrate how to apply the technique. 相似文献
9.
10.
Ioannis G. Tigelis Jean-Yves Raguin Zisis C. Ioannidis George P. Latsas Angelos J. Amditis 《International Journal of Infrared and Millimeter Waves》2008,29(4):432-442
The dispersion characteristics of a circular cylindrical waveguide with periodic surface corrugations consisting of rectangular
grooves with smoothing are examined using the Space Harmonic Method (SHM). The whole structure is divided into two regions,
one describing the propagation volume and one inside the grooves. In the first region, the Floquet theorem is applicable and
the field distribution is expressed as a summation of spatial Bloch components, whereas in the second one an appropriate Fourier
expansion of standing waves is used. Applying the boundary conditions an infinite system of equations is obtained, which is
solved numerically by truncation. Several cases are considered, including the limiting cases of a sinusoidal and a rectangular
corrugation profile, to check the accuracy of the method proposed as well as its dependence on the corrugation profile. Numerical
results are presented only for transverse magnetic modes, although the formalism can be easily extended to include all kinds
of waves that can in principle propagate in such a structure. 相似文献
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13.
Yang Yan Shenggang Liu 《International Journal of Infrared and Millimeter Waves》1999,20(10):1725-1730
The dispersion equation of electromagnetic wave is derived for corrugated waveguide filled with plasma immersed in magnetic field under assumption of small corrugation, the dispersion characteristics of low frequency plasma mode are calculated and analyzed, the dense spectrum of plasma mode is demonstrated. 相似文献
14.
In this paper, we show how the coupling of light into a photonic crystal waveguide can be greatly enhanced by creating a periodic modulation in the dielectric structure surrounding the entrance of the waveguide. In this way, surface modes supported by the system can funnel the light that impinges onto the surface into the interior of the waveguide. Moreover, we also demonstrate that the shape and direction of the beam that emerges from the structure can be tailored by constructing a periodic corrugation near the exit side of the waveguide. 相似文献
15.
Plasmonic waveguides and conventional dielectric waveguides have favorable characteristics in photonic integrated circuits. Typically, plasmonic waveguides can provide subwavelength mode confinement, as shown by their small mode area, whereas conventional dielectric waveguides guide light with low loss, as shown by their long propagation length. However, the simultaneous achievement of subwavelength mode confinement and low-loss propagation remains limited. In this paper, we propose a novel design of an alldielectric bowtie waveguide, which simultaneously exhibits both subwavelength mode confinement and theoretically lossless propagation. Contrary to traditional dielectric waveguides, where the guidance of light is based on total internal reflection, the principle of the all-dielectric bowtie waveguide is based on the combined use of the conservation of the normal component of the electric displacement and the tangential component of the electric field, such that it can achieve a mode area comparable to its plasmonic counterparts. The mode distribution in the all-dielectric bowtie waveguide can be precisely controlled by manipulating the geometric design. Our work shows that it is possible to achieve extreme light confinement by using dielectric instead of lossy metals. 相似文献
16.
M-Z光波导是聚合物电光调制器的重要结构单元。利用有效折射率法计算聚合物脊形波导的横向折射率分布,将三维光波场传播简化为二维传播。从导模满足的标量波动方程出发,结合透明边界条件,采用Crank-Nicholson差分格式,得出有限差分束传播法的基本计算格式。通过对M Z型波导结构中TM模的传播及损耗特性进行理论分析,系统地研究了脊宽、分支角等结构参数对损耗的影响。研究表明,有效折射率法与二维有限差分束传播法的结合可以较好地解决脊形M Z波导的设计问题。该方法具有精度高、计算量小及效率高等优点,为聚合物电光调制器的制备提供了理论依据。 相似文献
17.
提出了一种基于耦合介质纳米线的深亚波长局域波导,通过两根紧邻的高折射率介质纳米线的耦合,该波导可以将光场有效束缚在纳米线之间的低折射率纳米缝隙中. 计算模拟的结果表明,该波导的有效模场面积达到Λ20/200,比单根纳米线波导小一个数量级,这种深亚波长的模场束缚能力可以与表面等离激元混合波导相比拟. 计算模拟的结果还表明,纳米线可能带有的低折射率氧化膜、低折射率衬底的存在、以及纳米线间尺寸存在的一定差异对于该波导结构的实际应用都不会产生很大
关键词:
介质波导
亚波长局域
表面等离激元波导
纳米线 相似文献
18.
计算了同轴波纹慢波结构的色散特性,分析了波纹周期长度、波纹幅值大小以及同轴内导体半径对慢波结构色散特性的影响。研究表明内导体的存在使系统截止频率升高,系统尺寸可比普通波纹波导慢波系统更大, 并且可以采用大半径电子注并工作在低磁场状态。运用Magic软件对同轴波纹返波管进行了数值模拟, 发现同轴波导内场分布有利于注波互作用,在数值模拟基础上设计出高效率、低磁场的非均匀同轴波纹返波管,互作用效率达60%,聚束磁场小于1 T。 相似文献
19.
A new solving method of non-unifrom dielectric planar waveguide is presented in this paper. By applying this method to solving the problem of planar dielectric waveguide with arbitrary refractive index variation, the advantage of this new method is more evident. By dividing the waveguide into proper numbers and thickness of layers, we can transform the problem of non-uniform dielectric planar waveguide into the multilayer dielectric waveguide to calculate its propagation constantβ. 相似文献
20.
左手介质椭圆光波导基模传播特性 总被引:1,自引:0,他引:1
在椭圆柱坐标系中,采用分离变量方法,得出了左手介质椭圆光波导本征方程的近似解,通过数值计算,分析了椭圆波导偏心率、左手介质的电容率、磁导率对椭圆光波导基模传播特性的影响,并将左介质光波导与右手介质光波导基模特性进行对比,得出左手介质光波导的基模特性与右手介质光波导基模特性差别不大的结论. 相似文献