Excess Conductivity Analysis of Cu0.5Tl0.5Ba2Can−1CunO2n+4−δ (n = 2, 3, 4) Thin Films

Cu0.5Tl0.5Ba2Ca n−1Cu n O 2n+4−δ (n = 2, 3, 4) thin film samples have been investigated for excess conductivity analysis (fluctuation-induced conductivity (FIC)). The thin films are c-axis oriented and have shown the tetragonal structure in which the T c (R = 0) of the samples increases with an increasing number (n) of the CuO2 planes. The FIC analysis is carried out by following the Aslamazov-Larkin theory and in the critical regimes from the Ginzburg-Landau number. By employing the Ginzburg-Landau theory, we have calculated important superconductivity parameters. The values of ξ c(0), VF, and τ φ increase, but the inter-layer coupling (J) of CuO2 planes is suppressed with the increasing number of CuO2 planes in these samples. The λ pd, however, is suppressed, but the values of B c(T), B c1(T), and J c(0) increase with the increasing number of conducting planes in Cu0.5Tl0.5Ba2Ca n−1Cu n O 2n+4−δ (n = 2, 3, 4) samples. This demonstrates the increase in flux pinning characters that is most likely induced by thallium defects in the charge reservoir layer.