Optical Properties of Nano-circuits for Metallic and Non-Metallic Nanoparticles

Optical properties of the nanoparticles can be studied theoretically by using the lumped electronic components. The particles having >0 behaved as capacitor whereas for  <0 had inductor properties on the other hand the electric field perpendicular to the components then the properties of series combinations dominates and vice versa. A first principles electronic structure based method is presented to determine the equivalent circuit representations of nanostructured physical systems at optical frequencies, via a mapping of the effective permittivity calculated for a lattice of physical nano-elements using density functional theory to that calculated for a lattice of impedances using circuit theory. Specifically, it is shown that silicon nanowires and carbon nanotubes can be represented as series combinations of inductance, capacitance and resistance. It is anticipated that the generality of this approach will allow for an alternate description of physical systems at optical frequencies, and in the realization of novel opto and nanoelectronic devices, including negative refractive index materials.