• auxiliary differential equation (ADE);
  • finite-difference time-domain (FDTD);
  • chiral metamaterials;
  • cross-polarized;
  • negative phase velocity


Because the permittivity, permeability, and chirality parameters of chiral metamaterials (CMMs) are frequency dependent, the wave equations that describe the characters of electromagnetic wave propagation in CMMs are presented and discretized on the basis of auxiliary differential equation technique in finite-difference time-domain method. The total-field/scattered-field, Mur's first-order absorbing and dielectric boundary conditions for CMMs slab are discussed in the paper. Numerical results show that the cross-polarized reflected coefficient of the CMMs slab is zero. Negative index of refraction phenomenon and optical property of giant optical activity in CMMs slabs are illustrated with 1D auxiliary differential equation–finite-difference time-domain method. The effects to positive or negative phase velocity caused by media parameters of CMMs are studied. Copyright © 2013 John Wiley & Sons, Ltd.