Optical nonlocalities and additional waves in epsilon-near-zero metamaterials

Abstract

We analyze the optical properties of plasmonic nanorod metamaterials in the ε-near-zero regime and show, both theoretically and experimentally, that the performance of these composites is strongly affected by nonlocal response of the effective permittivity tensor. We provide the evidence of interference between main and additional waves propagating in the room-temperature nanorod metamaterials and develop an analytical description of this phenomenon. Additional waves are present in the majority of low-loss ε-near-zero structures and should be explicitly considered when designing applications of ε-near-zero composites, as they represent a separate communication channel. © 2009 The American Physical Society.