Analysis of Fluctuation Conductivity in Melt-Textured Dyba2cu3oy Superconductors

We evaluated the superconducting properties of DyBa2Cu3Ox (Dy123) with different amounts of Dy2BaCuO5 (Dy211) phase. The samples were melt-textured DyBaCuO superconductors, which were made from the mixtures in molar ratios of Dy123:Dy211=1:x (x=0.03, 0.05, 0.08 and 0.1). The temperature dependence of resistance of DyBaCuO superconductors on different amounts of 211 phase was measured. The data of fluctuation amplitude and the dimension of conduction were obtained from analyzing the fluctuation. The results show that coherence length obtained from this analysis becomes larger as amounts of 211 phase increase. The evidence is found that the pinning force in the sample is well correlated with the characteristic length of superconductivity.