Large multiseeded domains of (Y, RE)BaCuO obtained by the MUSLE technique

Abstract

The multiseeded seamless bulk technique (MUSLE) developed by Sawamura et al for Dy/Gd/Ho-BaCuO compositions have been adapted for Y-based superconductors. This method allows overcoming the major problem encountered with the multiseeding technique, which is the trapping of non superconducting phases between the different domains. The MUSLE process requires the choice of two compositions for the bi-layer system. The criterion is a sufficient difference in the peritectic decomposition temperatures. In this condition, the higher peritectic temperature layer serves as nucleating site for the final YRE123 domain. Differential thermal analyses have been performed to select suitable compositions of as the upper layer and YYb123 as the lower layer. The influence of (Y, RE)2BaCuO5 (YRE211) composition on the crystal growth rate and on the superconducting properties was also investigated. Finally, compositions and thermal cycle have been defined to texture 2 cm multiseeded bi-layers samples. Electrical properties, coupled with SEM observations reveal the sample quality.