Guided Modes in Negative Refractive Index Waveguides

A Supersymmetric Approach to the Problem of Micro-bending Attenuation in Optical Waveguides

Micro-bending is a well-known source of loss in optical waveguides. By treating the micro-bending as a stochastic process, the problem of loss mitigation can be modeled in terms of a Fokker-Planck equation. Given an initial refractive index profile, and taking micro-bending into account, we develop a formalism to derive a new refractive index profile which potentially results in less loss. Our formalism is based on applying the techniques of Supersymmetric Quantum Mechanics to a Fokker-Planck equation that is associated with a particular refractive index profile. We derive a non-linear differe…

通过滑移对称声子晶体波导同时操控电磁波与弹性波

Simultaneous manipulation of electromagnetic and elastic waves via glide symmetry phoxonic crystal waveguides

本文设计了一种滑移对称声子晶体波导，利用能带粘附效应实现电磁波与弹性波同时单模无间隙传播，并可通过调节滑移位错调控色散，为新型光力器件提供新途径。

When does the choice of the refractive index of a linear, homogeneous, isotropic, active, dielectric medium matter?

Two choices are possible for the refractive index of a linear, homogeneous, isotropic, active, dielectric material. Either of the choices is adequate for obtaining frequency-domain solutions for (i) scattering by slabs, spheres, and other objects of bounded extent; (ii) guided-wave propagation in homogeneously filled, cross-sectionally uniform, straight waveguide sections with perfectly conducting walls; and (iii) image formation due to flat lenses. The correct choice does matter for the half-space problem, but that problem is not realistic.

Guided Wave Propagation in Complex Curved Waveguides I: Method Introduction and Verification

A phenomenological method is developed to consider elastic guided wave propagation in complex curved waveguides. The theory on guided wave propagation in hollow circular cylinders is used in order to verify the method. The results are compared with solutions obtained by the Helmholtz decomposition method. The method given here is used to derive new analytical relations for torsional and longitudinal phase velocity dispersion curves. In addition, a new excitation method is proposed and examined for flexural modes. Some conceptual results and applications of the method are discussed.

Study on acoustic radiation impedance at aperture of a waveguide with circular cross section taking account of interaction between different guided modes

In this paper we simulated self- and mutual- acoustic impedances of guided modes at the aperture and estimated accuracy of the piston radiation approximation. We used the Rayleigh integral to simulate the interactions between different guided modes at the aperture, with low time-consuming. This kind of guided-wave technique can be utilized to solve problems in diverse fields of wave science such as acoustics, electromagnetism and optics. For acoustic waves emitted through a horn or a waveguide with an aperture much smaller than the wavelength, there are only plane wave modes in the waveguide a…

用于导波柔性偏振控制的全介质超构波导

All-dielectric meta-waveguides for flexible polarization control of guided light

本研究理论与实验发现了沿全介质超构表面及亚波长圆柱链传播的导波具有宽带TE-TM偏振简并现象，利用该近场偏振自由度实现了导波的四分之一波延迟偏振转换器，为平面光学应用铺平道路。