CZOCHRALSKI GROWTH OF RE3GA5SIO14 (RE = LA, PR, ND) SINGLE-CRYSTALS FOR THE ANALYSIS OF THE INFLUENCE OF RARE-EARTH SUBSTITUTION ON PIEZOELECTRICITY

Pr3Ga5SiO14 and Nd3Ga5SiO14 single crystals with constant diameter of 22 mm and lengths up to 145 mm have been grown by the Czochralski meth od, The phase identification, site occupancy of cations and axial latt ice parameter distribution were determined by X-ray analysis. The tran smission spectra within the 340-3200 nm wavelength region were measure d, The centre of interest are the piezoelectric properties of (2 (1) o ver bar 0) and (0 1 0) plates in comparison with former grown La3Ga5Si O14 crystals in order to find out the influence of the rare earth subs titution of La3+ by Pr3+ and Nd3+ on the piezoelectric strain constant d(11). A decrease of /d(11)/ with increasing atomic number was found giving the hint to the substitution of lanthanum by further elements w ith larger atomic radii, (C) 1998 Elsevier Science B.V. All rights res erved.