From RF Circuits to Optical Nanocircuits

A brief review of the concept of optical metatronics, that include metamaterial-inspired optical nanocircuitry, is presented. As processing speeds increase and higher and higher frequencies is used in circuitry, the need for circuits at the optical frequencies becomes more urgent. To get an idea of the quantitative values of such optical capacitors and inductors, it is assumed that a spherical particle has a diameter of 60 nm that is being illuminated with a He-Ne laser with a wavelength of 633 nm. Following analysis, it is noted that if this particle is made of SiO2, it will act as a lumped capacitor with capacitance of a few aF. The advantage of the notion of metatronics and the optical lumped nanocircuit is that a similar procedure can now be applied in the design of subwavelength optical filters using nanostructures as lumped circuit elements at optical frequencies.