In this work we present an introduction to photonic crystals by discussing the basic concepts and principles behind these artificial materials, as well as their abilities to control light and enable unusual optical phenomena. We will focus on specific examples including (1) negative refraction of light, (2) the superprism effect (anomalous electromagnetic dispersion), and (3) the possibility of superlensing (subwavelength focusing). These are very general results based on direct solutions of Maxwell’s equations, and can consequently be of relevance to many areas of science and technology.
We demonstrate optical bistability in a class of non-linear photonic crystal devices, through the use of detailed numerical experiments, and analytical theory. Our devices are shorter than the wavelength of light in length, they can operate with only a few mW of power, and can be faster than 1ps.