Temperature dependence of the electro-elastic properties of the monoclinic α-BiB₃O₆crystals

The monoclinic α-BiB₃O₆(α-BIBO) crystal has been actively studied for nonlinear optical applications, but with limited efforts for piezoelectric usages. In this work, the temperature dependence of the electro-elastic properties for α-BIBO crystal was investigated over the temperature range of −150–150 °C, where the α-BIBO crystal was found to possess low dielectric loss (<0.5%) and minimal variation of relative dielectric permittivities (<±10%). The temperature coefficients of elastic compliances were obtained to be on the order of 0.2–5.1 × 10⁻⁴/°C. Moreover, the α-BIBO crystal was determined to own good temperature stability of electromechanical properties, with coupling factors being 13–32.1% at room temperature, while the independent piezoelectric coefficients shifted differently as a function of temperature with the first order temperature coefficients evaluated to be on the order of −0.3–17.9 × 10⁻⁴/°C. The above temperature characteristics of the electro-elastic properties are important for designing piezoelectric sensors operational over a broad temperature range.