"Multifunctional Materials" is a topic of increasing impact in the field of the material science and technology. The multiferroism is a property of matter defined as the coexistence of two or more primary ferroic orders, the most important are ferromagnetism and ferroelectricity; when they coexist the multiferroic defined as MagnetoElectric. This property is of great interest for a number of applications, such as sensors, advanced electronics and spintronics.
Unfortunately, most of these materials can not be synthesized by standard techniques, because they require unusual thermodynamic conditions; it's often necessary to operate under high pressure in order to access the region where these interesting materials form. These conditions can be achieved at the HP Lab. at the IMEM-CNR in Parma, among the best equipped in Europe, where a number of facilities (Multi-Anvil and Piston-Cylinder presses, hydrothermal system, etc.) allow the material synthesis in a wide range of PT, up to 200 kbar and up to 2200° C, simultaneously. The presence of sophisticated equipment and the tradition in the study of innovative materials, make IMEM a center of excellence in the study of magnetoelectric materials.
The magnetoelectric multiferroic materials have very often a perovskite-type structure, due to the stringent constraints of symmetry and transport properties and dielectric properties. The perovskite is a high-density phase, thus stabilized under high pressure, and thanks to its tolerance with respect to chemical substitutions and structural distortions in the same phase cohexist properties that are normally competitive, as in the case of magnetism and ferroelectricity.
The development of complementary skills allow at IMEM to completely characterize the magnetoelectric materials, in term of structure and spatial symmetry, magnetic and electrical hysteresis (coercive field, saturation polarization and Tc) and direct measurement of the magneto-electric coupling (see figure).
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