This book presents transmission properties in one- and two-dimensional plasmonic metamaterials with periodically and randomly structured arrays of various shaped perforated-apertures on metallic surfaces in the terahertz region. At a specific frequency at which the plasmonic metamaterials are perfectly transparent, the metal materials become essentially invisible. In the case of one-dimensional arrays of slits, Fabry-Perot like shape resonance enhances transmission of nearby horizontal surface resonance by the periodicity. Whereas in the case of two-dimensional arrays of various shaped holes,...