Hexaferrites
Magnetoelectric Ferrites
- Grant Agency of the Academy of Sciences (2008-2009).
- Cooperation with Prof. Kimura, Division of Materials Physics, Osaka University, Japan
- Cooperation with Institute of Inorganic Chemistry ASCR
Y-type hexaferrite (BaSr)
2Zn
2Fe
12O
22 is a new promising magnetoelectric system in which the existence of electric polarization is conditioned by the noncollinear arrangement of the iron spins. In principle ferroelectricity might be present above the room temperature, but electrical conductivity prevents its observation at temperatures higher than approx. 130 K. Our recent calculations predict that conductivity and magnetism are strongly influenced by the distribution of iron and zinc in the tetrahedral sublattices of the hexaferrite. The aim of the project is to determine experimentally this distribution and to modify it by thermal treatment in order to widen out interval of ferroelectricity existence. Our effort will include preparation and characterization of polycrystalline and thin film samples, while single crystals are available thanks to our cooperation. Theoretical analysis will be an important counterpart of the experiment.