High-temperature electromechanical properties of strontium-doped langasite

The paper focuses on the investigation of the defect chemistry and transport mechanisms in strontium-doped langasite single crystals. It is found that strontium suppresses point defect relaxations observed in langasite up to about 400 °C. Thereby viscous damping could be lowered up to this temperature. Between about 400 and 600 °C strontium-doping does not impact the damping. Further, strontium dopants enhance the movement of oxygen ions via creation of oxygen vacancies above about 600 °C leading to a slight increase in damping. One concludes, that the relatively strong impact on damping exhibited by ionic defects can be utilized by the application of acceptor doping at elevated temperatures.