Abstract

We theoretically investigate the excitation of localized surface plasmon resonances (LSPRs) in semiconductor antennas at Terahertz (THz) frequencies. Such resonances induce considerable intensity enhancement of the highly localized electric field. At THz frequencies semiconductors show a Drude-like behavior, similarly to metals at optical frequencies. In fact, in the THz regime, semiconductors with narrow band gap (such as InSb) or doped semiconductor (e.g., Si) have a dielectric constant with a negative real component and a relatively small imaginary component. This is actually the dielectric signature of good metals in the visible and near infrared regimes. Therefore, in analogy to optical plasmonic metal antennas [1], THz plasmonic antennas can be made of semiconductors [2].

© 2009 IEEE