Isothermal growth of large YBa2Cu3O7−x single domains up to 93 mm (original) (raw)

The growth of YBa2Cu3Oz.x single domains larger than 30-40 mm by a classical Top Seeding Melt Texturing (TSMT) method appears to be difficult. Because of the very narrow solidification range between the onset of the nucleation from the seed and the nucleation of grains in the liquid, reaction with the substrate as well as uncontrolled thermal gradients introduce severe limitations to the growth. After suppressing nucleation from the substrate and improving the temperature homogeneity around the sample, the growth rate measured in situ was used to carefully adjust the process. A YBa2Cu307.x single domain has been grown up to 93 mm without applied thermal gradient nor large overheating. The texture is confirmed on a large volume by neutron scattering and an homogeneous 211 size distribution and content are found across the sample. This suggests that steady growth conditions have been maintained and that even larger samples could be grown.