A STUDY OF DIELECTRIC-PROPERTIES OF AMORPHOUS FERROELECTRIC LINBO3

Amorphous LiNbO3 was prepared using twin-roller melt quenching method, and temperature- and frequency-dependent dielectric constants were me asured. !Measuring temperature and frequency were varied from room tem perature to 701.2 degrees C and from 100 Hz to 1.5 x 10(7) Hz, respect ively. Ion hopping model was introduced to understand the dielectric b ehavior, and ''universal'' capacitors were used as a equivalent circui t. From the fitting the frequency-dependent dielectric constants at ea ch temperatures, it was revealed that the Li+ ion hopping is responsib le for the dielectric response of the amorphous LiNbO3. Frequency-depe ndent conductivities were measured at various temperatures and the hop ping behaviors of the Li+ ion is discussed. The a.c. conductivity foll ows the power low, and the d.c. conductivity follows the Arrhenius rel ation. The activation energy of the d.c. conductivity was 0.502 eV.