Percolation Effects in Composites Superconductor – Ferromagnetic Half-Metal

Abstract:

We investigated transport characteristics of composite that consist of the superconductor MgB₂ and ferromagnetic half-metallic nanoparticles La_0.7Ca_0.3MnO₃ (LCMO). The experiments were carried out in a wide temperature range with different volume content of the magnetic impurity. It was found that over 25% of the impurity manganite breaches percolation paths of the diboride magnesium. This leads to a considerable broadening of the MgB₂ superconducting transition and the formation of the network of contacts through the ferromagnetic inclusions. This result shows the possibility of the spin - activated surface realization on the superconductor - manganite boundary. It's allowing the free transition of Cooper pairs with s wave symmetry of the order parameter in a ferromagnet with 100% spin-polarized carriers.

• Periodical: Solid State Phenomena (Volume 215)
• Pages: 100-104
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.215.100
• Online since: April 2014
• Authors: Victoria V. Kononenko*, V.Yu. Tarenkov, A.I. Dyachenko, V.N. Varyukhin
• Keywords: Composite, Ferromagnetic Half-Metallic Nanoparticles, Percolation Cluster, Spin - Activated Surface, Superconductor

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