Electrooptic and Pyroelectric Materials

Ferroelectric materials may exhibit large electrooptic and pyroelectric effects. The electrooptic effect arises when an external electric field alters the charge distribution and moves ions. 

The PLZT ceramics show large changes in birefringence by switching the polarization and these materials are of potential use in optical memories and displays. However, the electrooptic properties utilized for such devices depend on the grain size.  

The dielectric materials important for many electronic and optical applications are acentric and many possess perovskite and perovskite-like structures. These structures are characterized by BO octahedra and a wide variety of phases can be obtained by virtue of the fact that the octahedra can be attached in several ways in building up a macroscopic phase. These structures afford considerable latitude for chemical substitution and thus for alteration of properties 

Nonlinear optical susceptibilities of materials can now be calculated from bond ionicity, atomic radii, and d-electron contribution to the bonding. 

An estimate of the theoretical breaking strength of a perfect solid based on the creation of two new surfaces shows that the maximum breaking strength is equal to where E, y, and 

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