En las fronteras de la Materia Condensada

Artificial periodically microstructured materials have attracted widespread interest in recent years because they offer an exciting new way to control the propagation of light. Such periodic materials, known as photonic crystals, can exhibit full photonic band gaps, that is, energy gaps of zero density of states. Electromagnetic waves with frequencies in the band gap cannot propagate through the crystal. Modifying the band gap structure, for instance, by introducing a defect or arrays of defects, produces effects similar to what can be done by doping electronic semiconductors. With this picture in mind, photonic crystals are to electromagnetic waves what semiconductors are to electrons. The purpose of this talk is to present an overview on how things work in a world ruled by Maxwell equations and Floquet-Bloch theorem, stressing analogies and differences between quantum mechanics of natural crystals and electromagnetism of artificial periodic dielectric media.