Dielectric Characterization of Ba(Fe_1/3 Nb_2/3)O₃ Perovskite

Ba(Fe_1/3 Nb_2/3)O₃ has been prepared by well established ceramic technique at 1100°C. It exists in disordered cubic phase with tetragonal superlattice structure. It exhibits single relaxation frequency at 533 KHz. The relaxation spectra imply the presence of interfacial polarization. The dielectric constant and relative loss have been determined as a function of temperature. It shows a diffused phase transition at 440 K. The measurements of Schottky barrier, bandgap and resistivity have also been carried out. On the basis of the observations the presence of dielectric microdomains is interpreted. The, observations are compared with Ba(Fe_1/2 Nb_1/2)O₃.

Keywords:

• Pervoskite
• dielectric
• interfacial polarization
• microdomains

Acknowledgments

Paper originally presented at AMF-4, Bangalore, India, December 12-15, 2003.