Flux growth and characterization of quasi cubic PZN-PT single crystals

Transparent single crystals of the perovskite Pb(Zn-1/3,Nb-2/3)O-3-PbTiO3 (PZN-PT) were grown from different lead fluxes in sealed platinum crucibles. A temperature gradient furnace was used (temperature gradient on crucible: 30-50 degreesC). Optimization of growth temperature range and cooling rates was carried out in fluxes of PbO, Pb3O4 with and without an addition of B2O3. The growth nature range was typically 1150 degreesC --> 930 degreesC (on crucible top) with cooling rates of 0.8 - 1 degreesC/h for the Pb3O4 flux. In these conditions, the best PZN-PT transparent single crystal was 4x4x2.5mm large and it showed a cubic habitus. The problem of crystal recovery from the residual flux Was solved by different methods based on liquid flux elimination at the end of the growth process.:The chemical composition and the homogeneity within the crystals were determined by electron probe micro-analysis and X-rays. Optical (polarized light microscope) and dielectric measurements were used for the characterization and determination of phase transitions, in single crystal with and without an electric field.