[摘要]:The magnetic hysteresis of MnxGa films exhibit remarkably large coercive fields as high as mu H-o(C) = 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 similar to 50-100 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. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3671329]