2005 Volume 74 Issue 2 Pages 173-179
Recently, a phenomenon called “negative refraction” has attracted many researchers in various fields. In this article, I review this topic, mainly concerning photonic crystals, and clarify how it works and how it appears. In addition, negative refraction in left-handed metamaterials and negative group velocity in the vicinity of strong resonance lines are discussed, particularly their relationship to negative refraction in photonic crystals. In all cases, negative refraction leads to various exotic light propagation phenomena that seem to contradict our commonsense, but they do not contradict any physical law. These phenomena reflect the uniqueness of light propagation in strongly dispersive media, which had previously been hardly accessible in conventional situations.
