Suppression of Superconductivity Due to Enhanced Co Doping in Cu0.5Tl0.5Ba2Ca2Cu3-y Co y O10-δ Superconductors

Fluctuation Induced Conductivity (FIC) of Co-doped Cu(0.5)Tl(0.5)Ba(2)Ca(2)Cu(3-y) Co (y) O(10-delta) (y=0, 0.05, 0.1, 0.5) Superconductors have been studied as to find the possible cause of T (c) suppression in these compounds. We used Aslamazov-Larkin (AL) and Lawrence-Donaich (LD) equations to analyze the FIC of our samples. In this regard, it is observed that the data seems to fit well with 3D (three-dimensional) AL equations. In addition, crossover temperature from 2D to 3D has been found. The width of the temperature window for 3D conductivity is continuously decreasing with enhanced Co concentration. The shrinking of 3D temperature region with increased Co doping can be correlated with the suppression of superconductivity. It is observed that the coherence length and th interplanar coupling strength have also been decreased with increased Co doping, consistent with the magnetic pair-breaking effect.