Oxygen Interstitial Dynamics in Bi(2)Sr(2)CaCu(2)O(8+delta) Oxides Measured by Mechanical Spectroscopy

• Autor(a) principal: Grandini, Carlos Roberto [UNESP]
• Data de Publicação: 2008
• Outros Autores: Ruiz, S. L M [UNESP], Silva, M. R. [UNESP], Gimenez, J. M. A. [UNESP], Rubo, Elisabete Aparecida Andrello [UNESP]
• Tipo de documento: Artigo de conferência
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.4028/www.scientific.net/MSF.591-593.634; http://hdl.handle.net/11449/132361
• topic: 2212 Oxides; Interstitial oxygen; Superconductivity; Critical temperatures; Electrical resistivities; Energy dispersions; Mechanical spectroscopies; Solid states; Stoichiometric mixtures; Temperature ranges; Torsion pendulums; X-ray diffractions; Activation energy; Copper oxides; Critical current density (superconductivity); Dynamics; Electric conductivity; Electric resistance; Lithium compounds; Oxides; Oxygen; Penetration depth (superconductivity); Powders; Scanning electron microscopy; Solid state reactions; Vibrations (mechanical); Nonmetals

Many researchers became interested in the discovery of Bi(2)Sr(2)CaCu(2)O(8+delta) oxides with critical temperature of around 80 K. It is known that the critical temperature is related to the CuO2 planes of the material. For this reason, the study of the interstitial oxygen in these oxides is of great relevance. The samples were prepared by means of conventional solid state reactions, through the stoichiometric mixture of precursory powders. After the sinterization, the samples were submitted to measurements of density, electrical resistivity, x-ray diffraction, scanning electron microscopy and energy dispersion spectroscopy, with the objective of performing their characterization. The measurements of mechanical spectroscopy were performed by a torsion pendulum. The results show three relaxation processes in the temperature range of 200 and 700 K, with activation energy of approximately 0.9 eV, which has been attributed to the dynamics of the interstitial oxygen present in the material.