Paraconductivity analysis for superconducting Bi–Sr–Ca–Cu–O whiskers

Abstract

By means of the paraconductivity analysis, we characterize superconducting Bi 2Sr 2CaCu 2O 8+ d whiskers which show a sharp resistive transition corresponding to the 2223 phase while identified to be mostly in the 2212 phase (99% or more) from XRD and SQUID measurements. The paraconductivity along the a-axis follows the behavior of the Aslamazov–Larkin theory, showing a dimensional crossover from 0D to 1D near T C. This implies that small islands of the 2223 phase distributed randomly in the 2212 phase could form quasi-1D dimensional percolation structure just above T C.