Local structure and magnetic properties study of Bi(Fe0.95Co0.05)O3 ceramics

The material BiFeO₃, as one of a few multiferroic materials, has attracted increasing interest due to its high ferroelectric Curie temperature (T_C ~1100K) and high antiferromagnetic Néel temperature (T_N ~ 650K), which appears to have the best potential applications such as information storage, spintronics, and sensors. Recently, cobalt was doped into BiFeO3 to enhance the ferromagnetism, but the origin of the enhancement of the saturated magnetization (M_s) is not clear. In this article, we study local structure of Bi(Fe_1-xCo_x)O₃ (x = 0, 0.05) so that we may find out the origin of the magnetic properties. Extended X-ray Absorption Fine Structure (EXAFS) has recently been developed for determining the inversion parameters of multiferroic materials, because this technique offers element specificity and local structure sensitivity, as well as inter-atomic distances, coordination number, and so on. The local structure information of atoms around a selected X-ray absorbing atom could be obtained by analyzing the EXAFS spectrum.