ABSTRACT
Inorganic electro-optic materials are competing with polymers for many applications. Liquid crystals constitute a well-established and rapidly expanding area and provide a common option for display devices. A useful property of many inorganic crystals is the wide transparency window covering the visible and near IR regions, as well as, often, part of the near UV. Moreover, they generally possess high cohesive energy and good thermal and mechanical stability. This is related to the fact that, at variance with organic materials with weak Van der Waals and hydrogen–bond interactions, inorganic materials present dominant ionic or covalent bonding. There is a large variety of useful inorganic electro-optic materials with different performance parameters such as spectral range, dielectric constant, electro-optic figure of merit, response time, refractive index tensor, etc. Therefore, each of them may find specific applications to cover a particular technological function. This entry reviews ferroelectric crystals, nonferroelectric dielectric crystals, transparent ceramics, transparent glasses, and semiconductors. It emphasizes new developments both in materials and applications.
