Correlation between magnetic and resistive transitions in a Bi sub(2)Sr sub(2)CaCu sub(2)O sub(8) ceramic

• Published in: Solid state communications Vol. 99; no. 8; pp. 531 - 536
• Main Authors: Burin, J P, Dehmej, J, Fouad, Y, Raboutou, A, Peyral, P, Lebeau, C, Rosenblatt, J, Carel, C, Ouammou, A
• Format: Journal Article
• Language: English
• Published: 01-01-1996
• ISSN: 0038-1098

Resistive and inductive transitions are measured on the same Bi sub(2)Sr sub(2)CaCu sub(2)O sub(8) ceramic. The transition curves present accidents which appear to be correlated and amenable to physical interpretation in quantitative agreement with a granular description. We consider two characteristic temperatures: T sub(s) which marks the appearance of superconductivity and T sub(C) < T sub(s) below which long-range coherence occur. In the paracoherent region T sub(C) < T < T sub(s) the excess conductivity is in good agreement with a power law Delta sigma infinity |1-T/T sub(c)| super(-y) with gamma identical with 2.7 while in the coherent region T < T sub(c) the field of first flux penetration is satisfactorily described by a power law H sub(1)(T) infinity (1-T/T sub(c)) super(n) with n identical with 2.7. The validity of this description is corroborated by the correct prediction, from resistivity data, of the distance d approximately 0.3 plus or minus 0.1 nm between CuO sub(2) layers in the unit cell.