High-homogeneity high-performance flux-grown Pb(Zn1/3Nb2/3)O3-(6-7)%PbTiO3 single crystals

Large-size, with > 35 mm edge length, high-quality PZN-PT single crystals of a range of compositions have been reproducibly grown from PbO flux with local point cooling and by engineering the isotherms of the solution to promote controlled (001) layer growth of the crystals. Twenty-four plate samples, 22(L) x 16(W) x 0.4(T) mm(3) in dimensions, were cut parallel to the prevalent (001) layer growth plane from two grown PZN-(6-7) %PT single crystals. The measurements have revealed high homogeneity in composition and poled properties both within individual plates and in between plates, with the Curie temperature T-c = 162-165 (less than or equal to+/-2 degreesC within plates), free dielectric constant K-T = 7200 +/- 6% (less than or equal to+10% within plates), dielectric loss (tan delta) < 0.013 and the thickness-mode electromechanical coupling factor k(t)=0.53 +/- 2.5% (<+/-3.0% within plates). Twenty k(33)-bars, about 4(L) x 4(W) x 12(T) mm(3) in dimensions, prepared from PZN-(6-7)%PT single crystals also display consistent and superior property values, with K-T approximate to 6100+/-13%; dielectric loss <0.010 (for all bars), k(33)=0.93-0.94 (for all bars) and d(33) approximate to 2850+/-10% pC/N. (C) 2004 Elsevier B.V. All rights reserved.