Characterization of new high-temperature piezoelectric single crystals in the system RCa4O(BO3)3 (R = Gd, Sm, La and Y)

• Applicant: Dr. Andrey Sotnikov
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2011 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 187989995

Piezoelectric crystals are key materials for modern solid state acoustics and acoustoelectronics. Of particular interest are materials those possess a reasonable piezoelectric response at very high temperatures (up to 10000 C and higher). The number of such crystals is vanishing and the study of their physical properties at very high temperatures is rather complex experimental problem. Notice that the knowledge of the high temperature properties is important not only for possible applications but also for basic understanding of materials behavior under critical conditions. The objective of the project is the study of material parameters (elastic, piezoelectric and dielectric constants, as well as electrical resistivity) of advanced piezoelectric crystals at very high temperatures (about 10000 C). The object under study is a new family of monoclinic piezoelectric oxoborates with the general formula RCa4O(BO3)3 (where R = Gd , Sm, La and Y). Material parameters of above single crystals at high temperatures are practically unknown. Moreover, room temperature material parameters of some oxoborates single crystals reported in literature are contradictory.

• DFG Programme: Research Grants