Band structures of mono- and diatomic metamaterials with inter-element coupling

Band structures of electro- and magnetoinductive waves propagating by virtue of interelement coupling on mono- and diatomic metamaterials are compared in a wide frequency range from MHz to THz. When the elements are scaled down to infrared frequencies, electrons' inertia results in dramatic reduction of magnetic coupling leaving the electric coupling unchanged. Narrowing of the passbands of slow waves of coupling can be prevented by employing metamaterial structures with electric coupling. Experimental and numerical studies confirm our analytical predictions.