Effects of dimensional crossover on the resistivity in Bi2Sr2CaCu2O8+x crystal

We report a study of the resistive transitions in Bi2Sr2CaCu2O8+x in the presence of an applied magnetic field (up to 12 T) at various field orientations. We focus our attention on the results obtained with orientations close to the parallelism to the (a,b) planes. We show that scaling arguments, typical of dissipative regimes independent of oriented defects, can explain qualitatively and semi-quantitatively the experimental findings, provided a 3D-2D crossover is assumed as the temperature is lowered, due to the variation of the out-of-plane coherence length. An estimate of the anisotropy in the 3D and 2D regions is given. © 1999 Published by Elsevier Science B.V. All rights reserved.