Growth and Characterization of Lead Titanate Single Crystals Grown in a Magnesia Single Crystal Crucible

The growth of PbTiO3 single crystals was studied using a MgO single crystal crucible by flux cooling method. As-grown PbTiO3 single crystals were used for measurements of relative dielectric constant, dielectric loss, dc-resistivity and pyroelectric coefficient. The results obtained are as follows. In this study the preparation conditions to obtain large PbTiO3 single crystals are summarized as follows. When the raw material mixed with the starting material/flux=PbTiO3/PbO (weight ratio)=0.339 was used, melted and cooled, a transparent PbTiO3 single crystal with a maximum size of 2.7×2.7×1.2mm was obtained at a cooling rate of 5°C/h in the range of 600° and 400°C near the Curie point, and 20°C/h in the ranges of 1100° to 600°C and 400°C to room temperature. Mg2+-doped PbTiO3 single crystals prepared in a MgO single crystal crucible were better than that in a platinum crucible. They were obtained in the middle part of the crucible at the upper part of flux as large plate-like crystals, containing 3000 to 5000ppm MgO from EPMA spot analysis of the crystal surface. From measurements of pyroelectric constant, the pyroelectric properties of Mg2+-doped PbTiO3 single crystals were elucidated. The present single crystals were found to be particularly superior with respect to dc-resistivity and dielectric loss to those of pure PbTiO3 single crystals.