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arXiv · 1111.6267

Large Coercivity in Nanostructured Rare-earth-free MnxGa Films

T. J. Nummy·S. P. Bennett·T. Cardinal·D. Heiman
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Abstract

The magnetic hysteresis of MnxGa films exhibit remarkably large coercive fields as high as 2.5 T when fabricated with nanoscale particles of a suitable size and orientation. This coercivity is an order of magnitude larger than in well-ordered epitaxial film counterparts and bulk materials. The enhanced coercivity is attributed to the combination of large magnetocrystalline anisotropy and ~ 50 nm size nanoparticles. The large coercivity is also replicated in the electrical properties through the anomalous Hall effect. The magnitude of the coercivity approaches that found in rare-earth magnets, making them attractive for rare-earth-free magnet applications.

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T. J. Nummy, S. P. Bennett, T. Cardinal, D. Heiman. 2011-11-27. Large Coercivity in Nanostructured Rare-earth-free MnxGa Films. https://doi.org/10.1063/1.3671329

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