Materials science includes those parts of chemistry and physics that deal with the properties of materials. It encompasses four classes of materials, the study of each of which may be considered a separate field: metals, ceramics, polymers and composites. Materials science is often referred to as materials science and engineering because it has many applications. This volume gathers important research from around the globe in this dynamic field including negative refraction of electromagnetic waves in semiconductor superlattices, and sapphire instruments for X-ray optics, types, properties and applications of sapphires and radioactive isotopes of Indium and their applications.