Animations obtained by the finite-difference time-domain method showing the backward wave propagation in double-negative single-layer waveguides

TL;DR

This paper uses FDTD simulations to visualize backward wave propagation in double-negative waveguides, highlighting their unique physical properties compared to conventional materials.

Contribution

It introduces FDTD animations demonstrating backward wave propagation in various double-negative waveguides, a novel visualization of their unusual electromagnetic behavior.

Findings

Backward wave propagation observed in DNG waveguides

Dispersion curves provided for different waveguide types

Transient signals exhibit unique propagation characteristics

Abstract

The materials having negative permittivity and negative permeability, which are labeled as double-negative (DNG) materials, have attracted much attention because of their unusual physical properties, which are different from those of conventional double-positive (DPS) materials. Animations obtained by the finite-difference time-domain method (FDTD) are provided showing how a transient sinusoidal signal that starts at t=0 propagates in the DPS and DNG waveguides. Three types of waveguides are considered: a slab or grounded slab inside the cladding medium and a parallel-plate waveguide filled with the slab. Dispersion curves in terms of normalized parameters are also provided.