Dynamical electric dipole theory for quantitatively describing coupled split-ring resonators

Metallic split-ring resonators possess dominant electric dipoles as well as considerable magnetic dipoles under proper excitations. Full-wave numerical approaches are frequently employed to simulate adjacent split-ring resonators, but simulations cannot explain the underlying physics. An analytical theory based on a dynamic electric dipole approximation is developed here. Detailed theory-simulation comparisons demonstrate that this theory can \textit{quantitatively} describe the interaction strength of coupled split-ring-resonators under certain circumstances.