The structural and magnetic investigation of (x) BiFe0.95Co0.05O3: (1-x) La0.7Ca0.3MnO3 composites

摘要

The structural and magnetic behaviors are studied in the composites (x) BiFe0.95Co0.05O3: (1-x) La0.7Ca0.3MnO3. An influence on the lattice parameters and magnetic states of BiFe0.95Co0.05O3 (BFCO) to the La0.7Ca0.3MnO3 (LCMO) are investigated. Although the variation of the relative X-ray intensity of LCMO to BFCO with composition (x) in XRD patterns and the randomly distributed small nanoparticle of LCMO (similar to 200 nm) mixed in the large nanoparticle of BFCO (similar to 900 nm) given by SEM images indicate an almost immiscibility of BFCO and LCMO in composites obtained by solid solution method, an obvious change of lattice parameters indicates their mutual influence on lattice structure. A detail magnetic investigation of the composites shows that the Griffiths phase is increased with increase of composition x due to the incorporation of ferromagnetism of BFCO to the paramagnetic phase of LCMO. An approximate magnetic phase diagram for the composites is established, which would be helpful for understanding the magnetic singularity of the composites with colossal magnetoresistance and multiferroics.