Use of Multi-Anvil Walker-type Press in growing novel complex materials

The study of complex functional materials is today one of the most relevant branches of the basic research in Materials Science. Unfortunately such phases are often characterized by complex structural constraints that often act as a limiting agent. For instance in the family of multiferroics, where the coexistence of two or more primary ferroic orders requires precise spatial and time inversion symmetry rules; on the other hand in High TC superconductors, the complex crystallographic arrangement is directly responsible for the Cooper-pairs transport mechanism. It is not casual that these two big classes of compounds are based on the perovskite structure: due to its large tolerance to structural distortions and chemical substitutions, perovskites allow to explore wide ranges of physical phenomena. In the synthesis of new perovskite-based compounds high pressure is a powerful tool because it permits to stabilize metastable phases, high density structures with unusual coordination numbers and high oxidation states. The Multi-Anvil Press Walker-type allow to perform solid state reactions under the application of high isotropic pressures (from 3 GPa up to 20 GPa) and at high temperatures (from 0 up to 2200°C). We present our laboratory potentiality in the production of complex perovskites; examples of the significant results in terms of the physical behaviour are capitalized to show also the set of proper characterization techniques developed.