Vortex matter and magnetic flux dynamics in superconductors

• Grant number: 15/06085-3
• Support Opportunities: Scholarships abroad - Research
• Start date: August 03, 2015
• End date: August 02, 2016
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Fabiano Colauto
• Grantee: Fabiano Colauto
• Host Investigator: Vitalii Vlasko-Vlasov
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Institution abroad: Argonne National Laboratory (ANL), United States

Abstract

Arresting vortices is crucial to application of superconductors, since dissipative process due to this dynamic limits the use of these materials. As solution, one needs to immobilize vortices in pinning centers. In HTS, such dynamics exhibit different regimes of Vortex Matter, whose properties are strongly affected by the interaction with the inherently complex medium of ceramic materials. Two regimes are more common in HTS: flux creep and flux flow. In superconducting films the flux dynamics arises as anomalous short-lived flux invasions, called avalanches. An effective technique to visualize magnetic field due to vortex arrangement in superconductors is Magneto-optical Imaging (MOI), which is very suitable for investigating the dynamics of Vortex Matter, because of its excellent temporal resolution. In order to control vortex dynamics, we intend to investigate, by mean of MOI, superconductors (SC) / ferromagnet (FM) hybrid systems, whose domain structures reduce flux dynamics and suppress thermomagnetic instabilities. In these systems occur strong magnetic attractions between vortices and domains, resulting the formation of coupled SC/FM domains. Such strategy to control the dynamics of vortex allows active and adaptive profiles of vortex pinning regions to tailor the electromagnetic behavior of type II superconductors. (AU)