  We will report on the electromagnetic response due to induced dipolar
currents in metamaterials of 2-dimensional array of metallic elements. Used as
frequency selectors, the metamaterial transmittance presents a single resonance
in the region from 1 to 8 THz that can be easily selected and scaled
maintaining unaltered the quality factor by choosing the size and shape of the
planar metallic element and exploiting the scalability properties of the
Maxwell equations. Basing on these studies, we have designed and tested a
series of simple and inexpensive frequency selective metamaterials fabricated
by using lithographic processes.
