手征等离子体波导导波控制特性的研究

应用纵向分量法推导出了完全填充手征等离子体金属圆波导的色散方程。通过数值求解完全填充手征等离子体金属圆波导的色散方程,得出了在不同条件下的几个低阶模的模式色散图。由此分析讨论了手征等离子体金属圆波导的基本传播特性并着重分析了手征导纳和外偏置磁场对完全填充手征等离子体金属圆波导的导波特性的影响并获得了有意义的结果。     

平板状双轴旋电磁手征波导中的耦合模理论

本文严格分析了一种新型双轴旋电磁手征波导中耦合模的传输特性。首先，给出了这种双各向异性手征波导中各横向场分量的纵向场分量表示式，由此得到了纵向场分量的耦合模方程，以及平板状双轴旋电磁手征波导中的色散方程。用数值方法研究了它的色散和截止特性，特别考察了双各向异性和手征性引起的波模分裂，转换效应。     

法拉第手征圆波导电中混合模的传输特性

本文研究了法拉第手征圆波导中混合模的传输特性，而在这种双各向异性复杂导波结构中，传输模的横向场分量仍可以用纵向场分量来表示，用Ｍｕｅｌｌｅｒ求根法分析了不同阶混合模的色散和衰减特征，以及不同本构参数对混合模传播特性的影响。     

法拉第手征圆波导中混合模的传输特性

本文研究了法拉第手征圆波导中混合模的传输特性，而在这种双各向异性复杂导波结构中，传输模的横向场分量仍可以用纵向场分量来表示，用Ｍｅｌｌｅｒ求根法分析了不同阶混合模的色散和衰减特征，以及不同本构参数对混合模传播特性的影响。     

手征等离子体波导电磁波传输特性

本文把电磁场分解成横向和纵向分量，导出了简明的普适性手征等离子体填充任意截面柱形波导的波动方程和横向纵向场量的关系式，导出了部分填充手征等离子体波导的色散方程。据此调查其电磁波的传播特性。     

手征等离子体波导理论

本文给出了手征等离子体波导（由在柱形波导中填充手征等离体材料构成）中横向场量与纵向场量之间的关系式，并给出了纵向场量的求解公式，作为示例，文中具体研究了平行板手征等离子体波导，得出了其中几个低次传播模式的色散特性曲线。     

多层手征介质填充圆波导的分析

本文利用递推本征函数法分析了多层手征介质填充圆波导的传播特性.文中给出了不同介质层中电磁场的递推关系,推导了N层手征介质填充圆波导色散特性的一般性计算公式.作为示例,文中还给出了对几种结构传播特性的计算结果.     

手征等离子体波导理论

本文给出了手征等离子体波导(由在柱形波导中填充手征等离子体材料构成)中横向场量与纵向场量之间的关系式,并给出了纵向场量的求解公式。作为示例,文中具体研究了平行板手征等离子体波导,得到了其中几个低次传播模式的色散特性曲线。     

椭圆手征波导的导模特性研究

该文首先对椭圆手征波导进行了解析求解,导出了模式场解及模式特征方程,然后用数值计算的方法研究了手征参数对椭圆手征波导中导模的色散曲线和截止波长的影响,发现在椭圆手征波导中导模的第一个模式会随手征参数的增加而不同。     

手征光纤中导模的色散特性

从手征介质中的电磁场本构关系出发，利用麦克斯韦方程组，对纤芯和包层都是手征介质构成的阶跃型手征光纤进行了解析求解，导出了模式场解和特征方程。用数值方法研究了纤芯和包层的手征导纳对手征光纤中导模的归一化传播常数、群延迟、波导色散等特性的影响。     

各向同性手征媒质均匀填充手征波导中的耦合波方程

本文从麦氏方程组和手征媒质的本构关系出发，运用耦合波理论，对各向同性手征媒质均匀填充的手征波导中存在的耦合孪生模式的电场和磁场矢量进行了推导并得到耦合波方程组的一般表达式，同时指出了在弱耦合近似条件下，应用微扰原理求解耦合波方程组的一般思路，为从耦合波的观点来分析手征波导中的各种不连续问题提供了一条新的理论途径。     

Mode orthogonality relations and field structure in chirowaveguides

By analyzing the vector and scalar equations for chirowaveguides, two forms of mode orthogonality relations are obtained: the vector formulated orthogonality and the scalar formulated orthogonality. The first one is applicable to the general case of open chiroplasma or chiroferrite waveguides. It is shown that for two parallel-plate isotropic chirowaveguides, these two forms of orthogonality relations differ. Based on mode orthogonality relations, it is shown that in chirowaveguides the polarization of so-called complex modes differs from that of propagating or evanescent modes. The correlation between field components of two complex modes that transfer active power flow in chirowaveguides is obtained     

Guided electromagnetic waves in gyrotropic chirowaveguides

The propagation characteristics of hybrid modes in the circular cylindrical and coaxial line gyrotropic chirowaveguides are studied using the technique of separation variables. First, the transverse components of electric and magnetic fields are expressed in terms of the longitudinal components of E and H¯. Then, numerical results are presented for the dispersion behavior and cut-off frequencies as well as the field distributions of hybrid EH_0,1 and HE_n,1, with the effects of different electromagnetic parameters of gyrotropic chiral material taken into consideration. It is shown that the process of mode bifurcation also takes place in the gyrotropic chirowaveguides; this is similar to the cases of reciprocal chirowaveguides. But, gyrotropic chirowaveguides are nonreciprocal bianisotropic devices     

Propagation analysis of chirowaveguides using the finite-elementmethod

Propagation analysis of chirowaveguides, i.e. waveguides including chiral media, are calculated using a generalization of the full vector finite-element formulation in terms of the electric and magnetic fields. The formulation permits numerous inhomogeneous waveguide structures of arbitrary linear composition, including chiral media, to be analyzed without any nonphysical, spurious modes. In the proposed formulation both the necessary conditions on the tangential field components and the additional conditions on the normal field components are automatically satisfied by the trial functions. In this way the dimension of the resulting sparse generalized eigenvalue problem is significantly reduced. The straightforward extension to the novel class of chirowaveguides, which exhibit a number of interesting new features, demonstrates the versatility of the formulation. The advantageous numerical properties are thus preserved. Numerical examples on both metal and dielectric chirowaveguides are given. The finite-element results are compared with exact solutions, and the correspondence is found to be excellent     

The theory of chirowaveguides

The theory of chirowaveguides is discussed, and their salient features are analyzed. It is shown that the Helmholtz equations for the longitudinal components of electric and magnetic fields in chirowaveguides are always coupled and that, consequently, in these waveguides individual transverse electric (TE), transverse magnetic (TM), or transverse electromagnetic (TEM) modes cannot be supported. As an illustrative example, the parallel-plate chirowaveguide is analyzed in detail and the corresponding dispersion relations, cutoff frequencies, and propagating and evanescent modes are obtained. In the dispersion (Brillouin) diagram for a chirowaveguide, three regions are identified: the fast-fast-wave region, the fast-slow-wave region and the slow-slow-wave region. For each of these regions, the electromagnetic field components in a parallel-plate chirowaveguide are analyzed and the electric field components are plotted. Potential applications of chirowaveguides in integrated optical devices, communications systems, and printed circuit antennas are mentioned     

Reflection and transmission of guided electromagnetic waves at anair-chiral interface and at a chiral slab in a parallel-plate waveguide

Recently, the concept of chirowaveguides, which exhibit some novel and interesting properties due to electromagnetic chirality, was introduced and studied elsewhere. In this paper, the authors analyze theoretically another problem associated with chirowaveguides, namely, the problem of reflection and transmission of guided waves at an air-chiral interface and at a chiral slab located transversely in a parallel-plate waveguide. The notable features and the role of chirality of the medium on the reflected and transmitted guided waves are discussed, and physical insights into these results are provided. It is found that since the guided modes inside the chiral region of the waveguide are hybrid, in order to satisfy the boundary conditions at interfaces, the reflected and transmitted guided modes in the air regions of the waveguides need to be of TE and TM modes. The motivation behind this study is the potential applications of this problem to the design of novel measurement techniques for determining material parameters of chiral composites     

The eigenfunction expansion of dyadic Green's functions forchirowaveguides

A general method of formulating eigenfunction expansion of dyadic Green's functions in lossless, reciprocal and homogeneous chirowaveguides is presented. Bohren's decomposition of the electromagnetic field is used to obtain the vector wave functions. The method of G¯¯_m is used to rigorously derive the magnetic and electric dyadic Green's functions. A specific application to the cylindrical chirowaveguide illustrates the method     

Network representation and transverse resonance for layeredchirowaveguides

This paper presents an equivalent network method for dispersion analysis of general chirowaveguides. First, wave propagation in each homogeneous layer is represented by two pairs of transmission lines, the matrix wave impedance is defined. Next, the transformation properties of the input impedance are established. It is then demonstrated that the transverse resonance condition involving the previously obtained matrix impedance leads to the dispersion equation for the waveguides. The numerical results show that this network approach is feasible and practicable     

Rectangular modes and dyadic Green's functions in a rectangularchirowaveguide. I. Theory

An analytic solution of electromagnetic-wave propagation in a rectangular chirowaveguide is represented in this paper in terms of spectral-domain dyadic Green's functions (DGF's) in a general form. The method used here is a combination of a wavefield decomposition method and DGF eigenfunction expansion technique. This DGF decomposition method avoids having to use the modified and normalized vector wave functions, which are found difficult to satisfy the boundary conditions of chirowaveguides in which the reconciliation of Dirichlet and Neumann conditions is impossible. On the other hand, this method can be generalized to a chirowaveguide of arbitrary cross section and is found reducible to a nonchiral case. It is observed that in a similar fashion to the conventional rectangular waveguide, the duality between the electric and magnetic types of DGF's in the rectangular chirowaveguide does not exist. To show the reducibility of the generalized DGF's for bi-isotropic media, we summarized the procedure of utilizing the formulas and proved in detail that the form of the DGF's can be reduced to that for chiral media and achiral (isotropic) media. Exactly the same DGF's are obtainable for the isotropic media by reducing the general formulas. The electric and magnetic fields in the rectangular chirowaveguide due to a point dipole excitation oriented in the y-direction are derived. The detailed numerical analysis includes the novel features of the dispersion relations, the effects of chirality on the novel features of the rectangular chirowaveguides, some newly discovered features, and vector field plots and contour plots of higher order modes of electric and magnetic fields