Some diffusive properties of oxygen in Y-Ba-Cu-O systems

D. Djurek; V. Manojlović; Z. Medunić; M. Prester; E. Babić; K. Zadro

doi:doi:10.1051/jp1:1992123

Numéro		J. Phys. I France Volume 2, Numéro 1, January 1992


Page(s)		63 - 67
DOI		https://doi.org/10.1051/jp1:1992123

DOI: 10.1051/jp1:1992123
J. Phys. I France 2 (1992) 63-67

Some diffusive properties of oxygen in Y-Ba-Cu-O systems

D. Djurek¹, V. Manojlovic¹, Z. Medunic¹, M. Prester², E. Babic³ and K. Zadro³

¹ Volta Applied Ceramics, 41000 Zagreb, Croatia, Yugoslavia
² Institute of Physics of the University of Zagreb, 41000 Zagreb, Croatia, Yugoslavia
³ Department of Physics, Faculty of Natural Sciences, 41000 Zagreb, Croatia, Yugoslavia

(Received 21 August 1991, accepted 4 October 1991)

Abstract
We have studied the diffusive properties of oxygen in Y-Ba-Cu-O systems at 940 $^{\circ}$ C by measurements of the resistive response time $\tau$ of the samples subjected to the step-like increase of the oxygen pressure $\Delta p_{{\rm O}_2}\sim 1$ to 5 bars. The superconducting (SC) transition widths $\Delta T_{\rm c}$ plotted versus inverse diffusion constant $D^{-1}\sim\tau$ obey the universal linear dependence. The characteristic protruded tail of the real part of AC susceptibility which exhibits the feature at 86 K is absent in samples with the nominal composition Y ₃Ba ₃Cu ₆O _x (Y-336) in the regime $\tau<3$ s as result of weakly connected grains of YBa ₂Cu ₃O $_{7-\delta}$ (Y-123) nucleated from decomposed Y-336 phase.