An enhanced finite difference time domain method for two dimensional Maxwell's equations

TL;DR

This paper introduces an improved finite-difference time-domain algorithm for 2D Maxwell's equations in inhomogeneous media, enhancing accuracy and ease of integration into existing FDTD software.

Contribution

The paper develops a new FDTD scheme based on integral Maxwell's equations, improving accuracy over previous methods for dielectric interfaces.

Findings

Achieves higher accuracy than contour-path and staircase methods

Validated with dielectric cylinder scattering and Mie theory

Simple structure allows easy integration into existing FDTD software

Abstract

An efficient finite-difference time-domain (FDTD) algorithm is built to solve the transverse electric 2D Maxwell's equations with inhomogeneous dielectric media where the electric fields are discontinuous across the dielectric interface. The new algorithm is derived based upon the integral version of the Maxwell's equations as well as the relationship between the electric fields across the interface. It is an improvement over the contour-path effective-permittivity algorithm by including some extra terms in the formulas. The scheme is validated in solving the scattering of a dielectric cylinder with exact solution from Mie theory and is then compared with the above contour-path method, the usual staircase and the volume-average method. The numerical results demonstrate that the new algorithm has achieved significant improvement in accuracy over the other methods. Furthermore, the algorithm has a simple structure and can be merged into any existing FDTD software package very easily.