Anomalous dielectric behavior and reversible pyroelectricity in roller-quenched LiNbO3 and LiTaO3 glass

Vitreous LiNbO3 and LiTaO3 have been prepared by roller quenching these compositions from the melt. The transparent glasses exhibit pronounced dielectric anomalies with peaks of ε≳105 close to the crystallization temperature which are not characteristic of the crystalline phase. Pyroelectricity is induced after cooling the glass in an electric field. The data are discussed in terms of a simple theoretical model for amorphous ferroelectricity and interfacial polarization due to localized ionic motion.