DIELECTRIC AND ELECTRO-OPTIC PROPERTIES OF LEAD MAGNESIUM NIOBATE

Abstract

Low-frequency dielectric constant measurements vs temperature and electric field indicate that the ferroelectric transition in Pb3MgNb2O9 is second order. The quadratic electro-optic coefficients in Pb3MgNb2O9 are approximately an order of magnitude smaller than those of KTN (KTa.65Nb.35O3); however, the electronic conduction effects and compositional inhomogeneity problems encountered in KTN are absent in Pb3MgNb2O9, thus making it a practically useful electro-optic material.