Elastic properties of tetragonal PbTiO₃ single crystals by Brillouin scattering

Brillouin light scattering was used to obtain the elastic and piezoelectric constants for tetragonal PbTiO₃ single crystals at room temperature. Approximately 170 measurements of longitudinal and transverse acoustic wave velocities were inverted using literature dielectric constant values to obtain the full set of elastic and piezoelectric constants. Our data indicate a greater electromechanical anisotropy in the polar c direction than previously reported, but are otherwise in general agreement with previous studies. We discuss briefly the degree to which individual elastic and piezoelectric constants are resolved.