Experimental evidence of the decoupling line in(Bi1.64Pb0.36)Sr

Abstract

Both in-plane ( ab ) and out-of-plane ( c ) resistivity measurements have been carried out on (Bi 1.64 Pb 0.36 )Sr 2 (Ca 0.79 Y 0.21 )Cu 2 O 8ϩ␦ single crystals with magnetic field applied along the c-axis direction. Studying the temperature dependence of the resistivity ratio ab / c , we identify at high temperature a pancake phase with the signature proposed by Koshelev. At lower temperature, we observe a thermally activated behavior which can be interpreted easily in the framework of a three-dimensional vortex loops model. We found that the high-temperature limit of the thermally activated behavior corresponds to the low-temperature limit of the Koshelev's prediction. This latter is also characterized by an onset of the in-plane resistivity drop. Consequently, our data suggest that this line is a dimensional crossover which describes the decoupling of the liquid state into a decoupled pancake state.

Effect Y substitution on the microstructure, transport and magnetic proprieties of Bi2Sr2Ca1Cu2O8+δ superconducting ceramics

“…In the last case, the resistivity shows an important enhancement before the sharp decrease of the superconducting transition. Such behavior, as shown by several authors [47][48][49][50][51][52], indicates a transition from a gas of 2D pancake vortices to a liquid of 3D vortices, and is above the irreversibility line in the (H,T) plane.…”

Vortex shear effects in layered superconductors

“…The interplane transport properties of high-T c superconductors have been a subject of intense research over the past decade, both theoretical 9,10 and experimental 2,4,[11][12][13] . This transport, being of Josephson nature, is determined by the phase coherence between the adjacent layers.…”

Deviations from plastic barriers inBi2Sr2CaCu2O8+δthin films

“…Considering the fact that many authors suggested U 0 ∝ (1 − t) β with β = 1 in Refs. [4,5,6,7,8,13,14,15], β = 1.5 in Refs. [6,9,10], β = 2 in Refs.…”