LAUSR

The (Cu0.5Tl0.5)Ba2Ca3Cu4O12−δ thin films were synthesized at 895, 905 and 920 °C. These films are c-axis oriented and have shown tetragonal structure. The samples have been investigated for excess conductivity analysis. The analyses are carried out by following Aslamazov–Larkin theory. It is observed that the values of ξc(0), vF, λp.d, J decrease, but that of Bc(T), Bc1(T), Jc(0) increase with the increase of synthesis temperature. However, with the post-annealing of the samples at 100, 300 and 400 °C, the values of ξc(0), vF, τϕ and J increase but, the values of Bc(T), Bc1(T) and Jc(0) suppress with the increasing annealing temperature. It is proposed that with the higher synthesis temperature thallium defects are created in the charge reservoir layer that act as pinning centers whereas with post-annealing of the samples oxygen defects are removed. The former enhances whereas the later promotes suppression of Bc(T), Bc1(T), Jc(0) parameters in (Cu0.5Tl0.5)Ba2Ca3Cu4O12−δ thin films.