No abstract

In this communication, we present some results on thermo-electric properties of various high temperature superconductors. We have performed measurements on three rare-earth based cuprate superconductors. All the superconductors were prepared using solid state reaction method. The XRD studies on the present samples indicate that all the samples are in single phase. We observe that among the rare-earths studied in the present work, Gd-123 has the highest value of Z. In fact around 200K, the Zvalue for GdBa2Cu3O7-δ (Gd-123) samples is about two times that of the other rare-earths like YBa2Cu3O7-δ and EuBa2Cu3O7-δ. However with Pr-doping at the rare-earth site, we get a different trend viz. the figure of merit for Eu0.95Pr0.05Ba2Cu3O7 (Eu-Pr5%) and Gd0.95Pr0.05Ba2Cu3O7 (Gd-Pr5%) samples is less than their respective pristine compounds. On contrary, an almost two-fold increase is seen in Y0.95Pr0.05Ba2Cu3O7(Y-Pr5%) sample compared to the pristine sample of this series.