Effect of finite conductivity on dispersion characteristics of grating waveguide

Abstract

We present here a systematic investigation of dielectric waveguide loaded with a metal-strip grating which is realistically characterized by a complex dielectric constant with a negative imaginary part to account for the finite conductivity of the metal strips. The method of mode matching is employed to solve such a boundary-value problem, and the effects of the structure parameters on the dispersion characteristics are critically examined, with a particular attention directed toward the attenuation constant due to the Bragg reflection, radiation and absorption of the grating waveguide.