Dielectric coaxial waveguide

Abstract

A nonlinear theory of relativistic klystrons connected to a coaxial waveguide Modal cutoff. dispersion. and attenuation characteristics for the dielectric coaxial waveguide (three interfaces) are presented for representative parameters. These properties change considerably as the guide geometry and dielectric properties are varied. Discussion of dielectric guide operation and comparison of a particular design with a metal waveguide is given. ---HEI2 ----EHI2 FIG. 2. Cutoff wave numbers t: j =t:3=2.55, 102=1.03. [Eq. (A15)].

Analytical Dispersion Equations of a Lossy Coaxial Waveguide in the Microwave and Visible Spectra

“…A lossy coaxial waveguide can be modeled using a multilayered dielectric coaxial waveguide [1,[6][7][8] as shown in Fig. 1, where the medium constants-, , and , ,can be any complex number.…”

“…The interesting point of the geometry shown in Fig. 1 is that a dielectric coaxial waveguide [1,[6][7][8] shown in Fig. 2 is entirely surrounded by the PEC boundary.…”

“…2 is entirely surrounded by the PEC boundary. It is known that unwanted multiple leaky modes [11] are inevitably generated in open magnetodielectric waveguides including dielectric coaxial structures [1,6] with an open boundary as shown in Fig. 2.…”

“…Therefore, it is of great importance to derive and formulate an exact and rigorous dispersion relation of the lossy coaxial waveguide, which can be modeled as a multilayered dielectric coaxial waveguide [1,[6][7][8]. A dielectric coaxial waveguide was analyzed using the boundary conditions of an open region [6] and an infinitely lossy outer conductor [7,8]. In the following sections, we apply a standard mode-matching technique [9] for analyzing a dielectric coaxial waveguide surrounded by the perfect electric conductor (PEC) boundary.…”

Photonic crystal structures with ultrahigh aspect ratio in lithium niobate fabricated by focused ion beam milling

“…Another potential approach is to replace cylindrical holes with coaxial structures which have been studied for decades. 15,16 More beam energy can be concen-trated in the ring area which results in reduced energy spread and total etching time during the FIB process, enabling small features and large etching depth simultaneously. In alldielectric coaxial frames, polarization can be maintained throughout propagation due to the radially symmetric electric field distribution.…”