Some modifications on metamaterials using simple short wire pairs

In this paper, we propose a structure for metamaterials that is based on a previously introduced structure using a pair of short strips. In our proposed structure, the pair of short strips is replaced by four pairs of short strips of narrower widths and different lengths. As a result, instead of one magnetic resonant frequency, four magnetic resonant frequencies are created. By choosing appropriate lengths for the four strips, the four resonant frequencies are put close to each other and their spectrums have a slight overlap. As a result, the negative index of refraction bandwidth of the modified structure is increased three times compared to the same parameter in the original structure. Also, because of narrower widths of the short strips, the average transmission coefficient in the negative index of refraction region is increased from −5.39dB to −3.23dB for the proposed structure.