Ribbon-Ring 3D Design of the Metamaterial SRR Element

The paper proposes variants of 3D models of split ring resonators (SRR) based on ring structures as unit cells of doubly negative (DNG) metamaterials. Evaluation of the efficiency of the synthesized 3D SRR variants is based on determining their relative bandwidth, for which the real part of permittivity and permeability are negative. To analyze the electromagnetic properties of the proposed 3D SRR structures, numerical simulation in Ansys EM Suite was used. In the course of the research, an available set of geometric parameters that affect the width of the binegative zone in the low-frequency region of the spectrum was analyzed: the angles of deviation of the cuts in the rings from the vertical, the width of these cuts, variations in the cross-sectional dimensions of the perpendicular conductor and its displacement relative to the center of the rings. Nontraditional types of conductors were also studied, in particular options for the form in the form of a dumbbell and the use of a fractal tree. At the final stage of research, the main efforts were focused on the analysis of the influence on the frequency properties of the metamaterial unit cell model of the mutual displacement of the SRR rings relative to the middle of the conductor length and their inclination angles. As a result, the maximum relative frequency band of the binegative zone was reached, which is equal to 1.99995. This is superior to the previously obtained result for 3D SRR with square frames, for which this value corresponds to 1.9.