Backward wave eigenanalysis of a tuneable two-dimensional array of wires covered with magnetized ferrite

An eigenanalysis of an array of periodically located wires covered with axially magnetized ferrites is presented. The interest in this structure stems from our previous analytical study which revealed that such a wire may support backward surface and possibly backward leaky waves. It is thus expected that a periodic array of these ferrite loaded wires may behave as a backward wave media offering an equivalent negative index of refraction as well as electromagnetic band gaps. These possibilities are examined herein by extending our previous two - dimensional curvilinear frequency domain finite difference method (FDFD) toward the eigenanalysis of periodic structures. Initially, the periodicity is accounted through periodic boundary conditions, while latter the related Floquet expansion will be introduced within the FDFD formulation.