INVESTIGADORES
SERQUIS Adriana Cristina
artículos
Título:
Oxygen content, thermodynamic stability, and superconductivity of Hg1-χReχBa2CuO 4+δ
Autor/es:
A. SERQUIS; A.CANEIRO; A. BASSET; S. SHORT; J.P. HODGES; J. JORGENSEN
Revista:
PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS
Editorial:
American Physical Society
Referencias:
Año: 2000 vol. 63 p. 145080 - 145089
ISSN:
0163-1829
Resumen:
The oxygen nonstoichiometry of single phase (Hg, Re)-1201 samples was studied by high-temperature thermodynamic techniques. The relevant structural features and the oxygen occupancy numbers were determined by Rietveld refinements using x-ray and neutron powder diffraction data. Underdoped and overdoped samples for different Re contents obtained by changing oxygen content through suitable post annealing treatments enable us to analyze the effect of both substitutions on Tc. The Re doping increases the thermodynamic stability of the Hg-1201 phase due to the incorporation of strongly bonded oxygen atoms. The Re incorporation also makes it possible to easily reach the overdoped regime, without appreciably affecting the maximum Tc. The slight decrease of the maximum Tc may be due to the cation disorder introduced by Re. The effect of extra oxygen in the (Hg,Re)Oδ layer on the Tc of Hg-1201 compound is discussed.