Unconventional superconducting granularity of the Y/sub 1-x/Pr/sub x/Ba/sub 2/Cu/sub 3/O/sub 7-[delta]/ compound

• Autor(a) principal: Barros, Fábio Martins
• Data de Publicação: 2006
• Outros Autores: Pureur Neto, Paulo, Schaf, Jacob, Fabris, Frederik Wolff, Vieira, Valdemar das Neves, Jurelo, Alcione Roberto, Cantão, Mauricio Pereira
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/109094
• topic: Compostos de bário; Supercondutores de alta temperatura; Compostos de ítrio

We report on fluctuation magnetoconductivity and magnetic irreversibility of Y1−xPrxBa2Cu3O7− single crystals and a polycrystalline sample. Although our samples are all single phase orthorhombic and the single crystals show no sign of structural inhomogeneity, all the samples exhibit two close and sharp genuine superconducting transitions. On the other hand, while the resistive transition of the polycrystalline sample exhibits in addition a coherence transition characteristic of a granular superconductor and the magnetic irreversibility displays the signature of the intergrain flux dynamics, the single crystals show no sign of these features. In view of these facts, we conclude that the well characterized split superconducting transition must result from a peculiar phase separation related with oxygen doping.