Elastic constants of multidomain LiTaO3 crystal

All the independent components of the elastic constant tensor of multidomain LiTaO3 crystal were determined by measuring bulk acoustic wave velocities and density for five multidomain LiTaO3 substrates perfectly depoled by heat treatment. Comparing these determined constants with the elastic constants of single-domain LiTaO3 crystal revealed that the elastic constants of multidomain crystal cij differ from both the elastic constants at constant electric field cijE and those at constant electric displacement cijD for single-domain crystal. The angular dependences of leaky surface acoustic wave velocity were measured on single and multidomain 36°Y-cut LiTaO3 substrates by line-focus-beam acoustic microscopy and compared with the calculated results using the determined constants. The measured results agreed well with the calculated results. The constants will be used to enhance theoretical understanding of the elastic properties of residual multidomains.