We provide electrical circuit descriptions for bulk plasmons, single surface plasmons, and parallel-plate plasmons. Simple circuits can reproduce the exactly known frequency versus wave-vector dispersion relations for all these cases, with reasonable accuracy. The circuit paradigm directly provides a characteristic wave-impedance, Z o , that is rarely discussed in the context of plasmonics. The case of a single-surface-plasmon is particularly interesting since it can be modeled as a transmission line, even though there is no return current conductor. The capacitance/unit length and the Faraday inductance/unit length, of a flat metal surface, are C'=2ε o kW, and L'=µ o /2kW respectively, (where k is the wave-vector, and W is the width of the flat metal surface). We believe that many other metal-optic geometries can be described within the circuit paradigm, with the prerequisite that the distributed capacitance and inductance must be calculated for each particular geometry.

Focusing electromagnetic energy to subwavelength dimensions has become an increasingly active field of research for a variety of applications such as heat-assisted magnetic recording, nanolithography, and nanoscale optical characterization of biological cells and single molecules using the near-field scanning optical microscopy technique. Double-sided surface plasmons in a metal-insulator-metal (MIM) geometry can have very small wavelengths for dielectric of thickness of less than 10 nm. A tapered dielectric structure sandwiched between metal can be used to efficiently couple electromagnetic energy from free space photons to the plasmonic wavelengths at the nanoscale. In this paper, we present the fabrication and characterization of a novel MIM plasmonic lens structure.

The continued scaling of integrated circuits will require advances in intra-chip interconnect technology to minimize delay, density of energy dissipation and cross-talk. We present the first quantitative comparison between the performance of metal wire interconnects, operated in the traditional manner by electric charge and discharge, versus the performance of metal wires operated as surface plasmon waveguides. Surface plasmon wire waveguides have the potential to reduce signal delay, but the high confinement required for low cross-talk amongst high density plasmon wire interconnects significantly increases energy dissipation per transmitted bit, above and beyond that required for electric charge/discharge interconnects at the same density.

The efficient generation of surface plasmons from free space optical waves is still an open problem in the field. Here we present a methodology and optimized design for a grating coupler. The photoexcitation of surface plasmons at an Ag-SiO 2 interface is numerically demonstrated to yield greater than 50% coupling from a Gaussian beam into surface plasmon voltages and currents.