Structural and mechanical stability of La3Ga5.5Ta0.5O14 single crystal under hydrostatic pressure.
Résumé
The high pressure structural and elastic behaviour of LGT single crystal has been explored. The phase diagram has been investigated up to 20 GPa by x-ray diffraction and the equation of state deduced. The complete set of second order elastic constants (S.O.E.C.) and their pressure dependence have been determined by bulk acoustic wave measurements up to 8 GPa. The bulk and linear moduli and their pressure variations have been calculated and compared to values obtained by x-ray diffraction. The stability Born criteria have been deduced.