NONLINEAR ELASTIC PROPERTIES OF THE PIEZOELECTRIC CRYSTAL: GaPO_4

摘要

The elastic properties of the piezoelectric crystal GaPO_4 have been investigated at high pressure (and ordinary temperature) and at low temperature (under ordinary pressure).The pressure dependence of the elastic constants -nonlinear behaviour-shows that the crystal undergoes a structural phase transition around 14 GPa. This observation is tentatively correlated with a potential instability observed at low temperature (50 K).