7th INTERNATIONAL CONFERENCE ON FERRITES

J. Phys. IV France 07 (1997) C1-493-C1-494
DOI: 10.1051/jp4:19971201

Amorphous Oxide Films of the Bi₂O₃-Fe₂O₃-PbTiO₃ System Coexisting Ferromagnetism and Ferroelectricity Prepared by Gel-Coating

T. Fujii¹, T. Wada¹, Y. Tokunaga¹, K. Kawahito¹, M. Inoue¹, A. Kajima², B. Jeyadevan³ and T. Tohji<sup>3

1</sup>  Department of Electrical and Electronic Engineering, Toyohashi University of Technology, 1-1 Hibariga-oka, Tempaku-cho, Toyohashi 441, Japan
²  Department of Electrical Engineering, Kitakyushu National College of Technology, 5-20-1, Shii, Kokura-Minami-ku, Kitakyushu 803, Japan
³  Department of Resources Engineering, Faculty of Engineering, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai 980-77, Japan

Abstract
Magnetic and dielectric properties of films with the ternary oxide system Bi₂O₃-Fe₂O₃-PbTiO₃ prepared by coating gel-solutions synthesized by the glycol-gel process on either glass plates or low resistivity Si-wafers were investigated. It was found that films with the Fe₂O₃-molar concentration around 70% exhibit ferromagnetic as well as ferroelectric behaviors simultaneously above room temperature retaining amorphous state from x-ray diffraction even after annealed at 700°C in air. The microstructure of the films was examined by EXAFS and was confirmed to be in a strongly disordered state. These pronounced properties are supposed to arise from a sort of excessively frustrated spin glasses.

© EDP Sciences 1997