AN ULTRA-LOW LOSS SPLIT RING RESONATOR BY SUPPRESSING THE ELECTRIC DIPOLE MOMENT APPROACH

We propose an effective way to realize the ultra-low loss in a split ring resonator (SRR) by suppressing the electric dipole moment approach. To tremendously reduce the loss, the loss mechanism of the SRR is theoretically analyzed in detail. The nonuniform current distribution on the SRR loop results in the residual electric dipole moment and thus brings the high radiation losses. Three different SRR configurations that the lumped capacitor, the distributed capacitor and the dielectric medium are incorporated into the SRR metamaterial are conceived, by which the uniform current distribution can be observed. This leads to in a finite bandwidth deviated from the resonance frequency where the SRRʹs loss performance dramatically improves owing to suppression of the residual electric dipole moment. The proposed the loss reduction mechanism has potential applications in negative and zero index memataterials, especially at THz frequencies and in the optical regime.