Fluctuation-induced conductivity of polycrystalline Gd1-χCeχBa2Cu3O7-δ superconductor



Título del documento: Fluctuation-induced conductivity of polycrystalline Gd1-χCeχBa2Cu3O7-δ superconductor
Revue: Revista mexicana de física
Base de datos: PERIÓDICA
Número de sistema: 000363621
ISSN: 0035-001X
Autores: 1
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Instituciones: 1Universidade Estadual de Ponta Grossa, Departamento de Física, Ponta Grossa, Parana. Brasil
Año:
Periodo: Oct
Volumen: 58
Número: 5
Paginación: 404-410
País: México
Idioma: Inglés
Tipo de documento: Artículo
Enfoque: Analítico, teórico
Resumen en inglés This paper reports on measurements of the resistive transition in polycrystalline Gd1-χ Ceχ Ba2 Cu3 O7-δ samples (x = 0.000, 0.025 and 0.050). The samples were produced by a standard solid state reaction method and in two different thermal routes. The microstructure was analyzed by X-ray diffraction. The samples were considered homogeneous since no extra peaks due to impurity phase were observed. To identify power-law divergences in conductivity, the results were analyzed in terms of the temperature derivative of the resistivity and the logarithmic temperature derivative of the conductivity (d ln (Δσ) /dT). From the results, the occurrence of a two-stage transition besides the pairing transition splitting for sample with x = 0.050 was observed. Such splitting was associated with Ce doping and related with the occurrence of a phase separation. In the normal phase, Gaussian and critical fluctuations conductivity regimes were identified. Ón approaching the zero resistance state, our results showed a power-law behavior that corresponds to a phase transition from a paracoherent to a coherent state of the granular array
Disciplinas: Física y astronomía
Palabras clave: Física de materia condensada,
Superconductor de alta temperatura,
Policristales,
Gadolinio,
Cerio,
Fenómeno crítico,
Efectos de fluctuación
Keyword: Physics and astronomy,
Condensed matter physics,
High-TC Superconductor,
Polycrystals,
Gadolinium,
Cerium,
Critical phenomena,
Fluctuation Effects
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