Crystal growth and dielectric properties of solid solutions of Pb(Yb1/2Nb1/2)O3-PbTiO3 with a high Curie temperature near a morphotropic phase boundary

The Pb(Yb1/2Nb1/2)O-3-PbTiO3 (PYN-PT) binary system single crystal near the morphotropic phase boundary (MPB) composition with (100) planes of 1-2 mm length, on one side was successfully grown by the flux method using PbO-PbF2-B2O3 flux. The PYN-PT(47/53) single crystal was found, by simultaneous microdifferential thermal analysis and thermogravimetric analysis, to show a peritectic melting point at 1205 degreesC with a decomposition of the perovskite crystals into a pyrochlore phase and a liquidus point at 1253 degreesC. The structure of the PYN-PT (47/53) single crystal was determined by X-ray diffraction study to be tetragonal with a = 4.05 +/- 0.01 A and c = 4.14 +/- 0.01 A at room temperature. The PYN-PT single crystal shows the maximum value of the relative permittivity epsilon (r) of 16000 at 1 kHz at a Curie temperature T-c of 404 degreesC, which is as high as that in the Pb(Zr,Ti)O-3 system near the MPB and the value of the remanent polarization P-r of about 26 muC/cm(2) at 140 degreesC.