Structural phase transitions of multiferroic Bi0.7La0.3FeO3

Bi0.7La0.3FeO3 has received special attention in the last years, since it exhibits ferroelectricity and ferromagnetism at room temperature. Issues including understanding of the mechanisms related to ferroelectric and magnetic phase transitions and the correlation of structure, magnetism, and ferroelectricity are still under debate. Though, first PND data obtained in ISIS allow for an acceptable discussion of its structure, key information is still missing. The aim of this proposal is to carry out a high-resolution neutron diffraction experiment in HRPD across the phase transition, to ascertain crucial details of its structure, closing in this way the first obtained HRPD data. From this study, we envisage to fully determining symmetry and lattice distortions towards phase transitions, and highlight the main underlying mechanisms, especially the role of spin-lattice coupling