Magnetic instabilities along the superconducting phase boundary of Nb/Ni multilayers

We report vibrating reed and superconducting quantum interference device magnetometer data that exhibit prominent dips or oscillations of the superconducting (SC) onset temperature, Delta T(C)(H)approximate to 0.01-0.7 K, for a [Nb(23 nm)/Ni(5 nm)](5) multilayer (ML) in dc magnetic fields applied ne...

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Detalles Bibliográficos
Autores: Joshi, Amish G, Kryukov, Sergiy A., De Long, Lance E., González Herrera, Elvira María, Navarro Palma, Elena, Villegas, Javier E., Vicent López, José Luis
Tipo de recurso: artículo
Fecha de publicación:2007
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/52121
Acceso en línea:https://hdl.handle.net/20.500.14352/52121
Access Level:acceso abierto
Palabra clave:538.9
Superlattices
Transition
Vortices
Lattices
State
Field
Física de materiales
Física del estado sólido
2211 Física del Estado Sólido
Descripción
Sumario:We report vibrating reed and superconducting quantum interference device magnetometer data that exhibit prominent dips or oscillations of the superconducting (SC) onset temperature, Delta T(C)(H)approximate to 0.01-0.7 K, for a [Nb(23 nm)/Ni(5 nm)](5) multilayer (ML) in dc magnetic fields applied nearly parallel to the ML plane. The vibrating reed data exhibit reproducible structures below T(C) that may reflect multiple SC transitions, but they are sensitive to ac field amplitude and dc field orientation. This striking behavior poses challenges for theoretical and experimental investigations of interfaces between SC and ferromagnetic layers that involve magnetic pair breaking effects, "pi phase shifts" of the SC order parameter, and exotic ("LOFF") pairing states. Alternatively, the anomalies may mark dynamical instabilities within a confined, strongly anisotropic Abrikosov vortex lattice.