Inhibiting Left-Handed Wave Propagation by a Band Gap of Stacked Cut-Off Metallic Hole Arrays

In this letter, the behavior of a recently reported left-handed metamaterial working at millimeter-wave frequencies is analyzed. The metamaterial is built by the periodic stacking of metallic plates with sub-wavelength hole arrays that show extraordinary optical transmission. If the longitudinal period of the stacked structure is chosen adequately, it is possible to mold the electromagnetic wave propagation inside the structure from right-handed to left-handed. The transmission response of the fabricated prototype has been measured with a millimeter wave quasioptical vector network analyzer in the range between 40 GHz and 110 GHz confirming the possibility to tune the left-handed or right handed characteristics of the waves propagating there. These results can give rise to interesting applications such as novel lenses and other quasioptical structures