JOSEPHSON COUPLING STRENGTHS AND OVERLAPPING OF DIMENSIONS IN THE CROSSOVER REGION IN IRRADIATED MULTIPERIODIC HIGH-Tc SUPERCONDUCTORS

Abstract

We have bombarded (Bi,Pb)-2223 superconductors with 40 MeV α-particles to study the effect of irradiation on the dimensional crossover in fluctuation-induced conductivity. The pair-breaking parameter decreases with the irradiation and suppression of the critical temperature is obtained. The structural modification of the layer in the high-T c superconductors induced by irradiation affects the extent of the overlapping region in the process of dimensional crossover. The width of the overlapping regime is evaluated for the various doses of irradiation using the different possible relations for the normal state resistivity. The variation of the transition width (Δ T0) with the increase in dose of irradiation is discussed in terms of modifications of interlayer and intralayer Josephson coupling strengths.