Nanocircuit elements, nano-transmission lines and nano-antennas using plasmonic materials in the optical domain

Optical wave interaction with metallic nanoparticles is one of the interesting problems in nanotechnology and nanophotonics. For certain noble metals, the plasma frequency is in the visible or ultraviolet wavelengths, and therefore their permittivity have negative real parts in the optical frequencies. These metals behave as plasmonic materials, and as a result, their interaction with optical signals involves surface plasmon resonances. Using such plasmonic materials as nanocircuit elements, this paper describes a nano-transmission line provide a guided-wave structure in the optical regime with a lateral cross section far less than the operating wavelength, analogous to the conventional transmission line in the microwave regime. Nano-antennas, which are nanometer-sized transmitting and receiving systems, are also discussed.