Electromagnetic Radiation in Nanostructures

Abstract

In the same way that we observe electronic properties to change from insulators to semiconductors, to metals, so we must expect light to be radically affected by the physical structure of a medium. Yablonovitch [1] has pointed out that, given the right structure, materials can mimic most of the electronic effects. For example we can have a ‘photonic insulator’ from which all light is excluded, even zero point fluctuations. The interior of such a material would be insulated from the influence of these frequencies of electromagnetic wave. This radical restructuring of the electromagnetic spectrum over large regions of space by a process that may be as simple as drilling holes will have important consequences for optoelectronics. In his original paper Yablonovitch considered loss-free dielectric structures, but metals also show dramatic effects when structured on a scale of nanometres and it is with metals that I shall be concerned in this paper.