ABSTRACT
This chapter explains the linear and quadratic electro-optic effects (Pockels and Kerr effects) that result from the nonlinear polarization of a medium in an applied electric field and discusses the field-induced changes of the index ellipsoid of electro-optic crystals and their dependence on the crystal symmetry. The longitudinal and transverse electro-optic effects in bismuth germanate oxide (BGO), a material displaying the electro-optic with a cubic crystal structure and frequently used in voltage sensors as a transducer element, serve as a perfect illustrative way to describe this phenomena. Next, the chapter presents criteria for the selection of appropriate transducer materials and identifies materials suited for voltage sensing by line integration of the field. A Table lists important electro-optic materials and their properties.
