Influence of the dielectric-spacer thickness on the left-handed behavior of fishnet metamaterial structure

We investigated the effects of dielectric-spacer thickness on the left-handed behavior of a symmetric fishnet-like metamaterial working at microwave frequency. The left-handed behavior was demonstrated and characterized by the standard retrieval procedure. The thickness of spacer was varied in order to examine the electromagnetic response of the fishnet structure. It was found that the changed thickness can cause different pictures of the left-handed behavior based on the electric-magnetic correlation.