Naslov
Effect of magnetic nanoparticle doping on MgB2 superconductor

Autori
Novosel, Nikolina ; Galic, Stipe ; Pajic, Damir ; Zadro, Kreso ; Babic, Emil

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Abstracts of The 11th European Conference on Applied Superconductivity / - Genova, 2013, 334-334

Skup
European Conference on Applied Superconductivity (11 ; 2013)

Mjesto i datum
Genova, Italija, 15.09.2013. - 19.09.2013

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
MgB2 wires; superconductivity; magnetic nanoparticles; flux pinning

Sažetak
We briefly review main results of our systematic study of the influence of magnetic nanoparticles (MNP) on electromagnetic properties of bulk MgB2 superconductor. In spite of conceptual importance (magnetic pinning of vortices, coexistence of magnetism and superconductivity, etc.) and technological potential (enhancement of electromagnetic properties, such as critical fields and current density), present experimental and theoretical results for the influence of MNPs on MgB2 are inconclusive [1, 2]. Thus, the aim of our ongoing systematic study is to shed more light on this topic. So far we prepared over seventy (70) Fe-sheathed MgB2 wires doped with different amounts of different types of MNPs (such as carbon protected pure ferromagnets, magnetic borides and ferrites) and annealed at 650°C and 750°C in a pure argon atmosphere. In order to assess also the effects of co-doping, both uncoated and coated (with silica or dextrin) MNPs with different size and shape have been employed. Generally, doping with MNPs suppresses superconducting transition temperature of MgB2 and the rate of suppression correlates with magnetization (M) of MNPs. Thus, higher MNP contents and/or MNPs with high M inevitably cause deterioration of electromagnetic properties of MgB2. However, light doping with few species of MNPs (such as Ni, NiCoB and dextrin coated Fe3O4 and NiFe2O4) caused enhancement of low temperature electromagnetic properties of MgB2. Best results obtained for carbon/dextrin coated MNPs indicate the potential of co-doping for improvement of superconducting properties and vortex pinning in MgB2. However, no real evidence for the magnetic pinning of vortices has been found. The results are compared with the literature reports for MNP doping of MgB2. [1] N. Novosel et al., Supercond. Sci. Technol. 25 (2012) 095018(9pp) [2] N. Novosel et al., J. Phys.: Conf. Ser. 234 (2010) 022027

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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