Increment of the collective pinning energy in Na1 − xCa x Fe2As2 single crystals with random point defects introduced by proton irradiation

We study the influence of random point defects introduced by 3 MeV proton irradiation (doses 1 × 1016 and 2 × 1016 cm2) on the vortex dynamics of Na x Ca1 − xFe2As2 (x = 0.5 and x = 0.75) single crystals. Our results indicate that the irradiation produces an enhancement of the critical current densi...

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Detalles Bibliográficos
Autores: Haberkorn, Nestor Fabian, Kim, Jeehoon, Maiorov, B., Usov, I., Chen, G. F., Yu, W., Civale, L.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2014
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/34218
Acceso en línea:http://hdl.handle.net/11336/34218
Access Level:acceso abierto
Palabra clave:Vortex Dynamics
Proton Irradiation
Iron Based Superconductors
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We study the influence of random point defects introduced by 3 MeV proton irradiation (doses 1 × 1016 and 2 × 1016 cm2) on the vortex dynamics of Na x Ca1 − xFe2As2 (x = 0.5 and x = 0.75) single crystals. Our results indicate that the irradiation produces an enhancement of the critical current density and a reduction of the creep rate in vortex relaxation. The plateau in the temperature dependence of vortex creep rate initially present in as-grown single crystals disappears after irradiation. This fact can be associated with a large increment of the collective pinning energy (from <100 to 350–400 K). On the other hand, Maley analysis indicates that after irradiation both samples present a glassy exponent μ close to the one expected in the so-called large bundle regime (μ ≈ 7/9) for random point defects.