Enhanced Interlayer Coupling of CuO2 Planes Promote the Superconducting Properties of Cu0.5Tl0.5Ba2-YSrYCa2Cu3O10-δ (Y=0, 0.15, 0.25) Samples

The CuTl-1223 superconducting samples, doping the Sr atom at Ba site, have been synthesized at 860oC pressure. The charge reservoir layer (CRL) of Cu0.5Tl0.5-1223 superconductor is modified by doping Sr atom. The decrease in c-axis length which is most probably due to smaller size of Sr atom as compared to Ba. The substitution of Sr atom at Ba is confirmed by the Fourier Transform Infrared Spectroscopy (FTIR). The critical temperatures i.e., Tc(R=0). Tconset are increased with the Sr content which shows that superconducting magnitude enhanced. The excess conductivity analysis has been done using Aslamazov-Larkin and Lawrance-Donaich models. The crossover temperatures i.e., TCR-3D=TG, T3D-2D and T2D-SWF and c-axis coherence length ξc(0) are slanted to lower values. Moreover, the inter-plane coupling (J) increases due to decrease in c-axis length. From fluctuations induced conductivity, it is found that there is an inverse relationship between critical temperatures and coherence length.