An Unconditionally Stable 1-D FDTD Algorithm for Modeling Chiral Media Based on Similar LOD Method

An unconditionally stable scheme, which employs a similar technique to the locally one-dimensional (LOD) method, is proposed to study the one-dimensional (1D) nondispersive chiral media. In the proposed scheme, the recent new mesh-dividing method for bi-isotropic media is used. The method regards the two terms on the right-hand side of the rearranged curl equations as two directions and uses the LOD algorithm to deal with the equivalent two-dimensional (2D) problem. Through Fourier stability analysis and numerical simulation, it is found that the time-step size is not restricted by the Courant-Friedrich-Levy (CFL) stability condition, hence the proposed scheme is unconditionally stable. Compared with the similar Alternating Direction Implicit (ADI) method, the proposed scheme has lighter calculation burden and higher accuracy.