High-homogeneity High-performance flux-grown Pb(Zn 1/3Nb 2/3)O 3–(6–7)%PbTiO 3 single crystals

Abstract

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 (0 0 1) layer growth of the crystals. Twenty-four plate samples, 22 L×16 w×0.4 T mm 3 in dimensions, were cut parallel to the prevalent (0 0 1) 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 (⩽±2 °C within plates), free dielectric constant K T = 7200 ± 6 % (⩽±10% within plates), dielectric loss (tan δ)<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×4 W×12 T mm 3 in dimensions, prepared from PZN–(6–7)%PT single crystals also display consistent and superior property values, with K T≈6100±13%; dielectric loss <0.010 (for all bars), k 33=0.93–0.94 (for all bars) and d 33≈2850±10% pC/N.