Vortex liquid entanglement in twinned YBa_2Cu_3O_7 /Y_2BaCuO_5 composite superconductors

The angular dependence of the in-plane resistivity ρ(T,H, θ) of melt textured YBa_2Cu_3O_7/Y_2BaCuO_5 composites has been measured in a large range of magnetic fields and temperatures and from them, the intrinsic anisotropy of the superconducting state has been verified following the anisotropic Gin...

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Detalles Bibliográficos
Autores: Puig, T., Galante, F., González Herrera, Elvira María, Vicent López, José Luis, Martínez, B., Obradors, X.
Tipo de recurso: artículo
Fecha de publicación:1999
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/60179
Acceso en línea:https://hdl.handle.net/20.500.14352/60179
Access Level:acceso abierto
Palabra clave:538.9
Single-crystal Yba2cu3o7-delta
Lattice-melting transition
High-temperature superconductors
High-Tc superconductors
Upper critical-field
Cu-O Crystals
YBa_2Cu_3O_7-Y_2bacuo5 composites
Anisotropic superconductors
Untwinned YBa_2Cu_3O_7-delta
Quenched disorder
Física de materiales
Física del estado sólido
2211 Física del Estado Sólido
Descripción
Sumario:The angular dependence of the in-plane resistivity ρ(T,H, θ) of melt textured YBa_2Cu_3O_7/Y_2BaCuO_5 composites has been measured in a large range of magnetic fields and temperatures and from them, the intrinsic anisotropy of the superconducting state has been verified following the anisotropic Ginzburg-Landau approach. The influence of correlated defects like twin boundaries and quenched disorder generated by Y_2BaCuO_5 precipitates on the pinning behavior of these composites in the liquid vortex state is analyzed, and the corresponding phase diagram is determined and compared to that of twinned single crystals. We show that the irreversibility line displays an upwards shift due to twin boundary pinning enabling to define a ''quenched'' Bose glass transition. A new region in the vortex liquid state is identified where twin boundary pinning defines a partially entangled liquid vortex state characterized by a short-range c-axis vortex coherence. The transition to the entangled liquid phase is experimentally determined. The relevance of this depinning line and its unique position with respect to twinned single crystals is discussed. [S0163- 1829(99)01741-5].