Fixation of Orientated L1₀-FePt Nanoparticles on Si Substrates

We developed a convenient and efficient method for fixing chemically-synthesized ferromagnetic L10-FePt nanoparticles on Si substrates with their easy axis oriented perpendicular to the substrate surface. This method enables fixation of the L10-FePt nanoparticles on Au-coated Si substrates by using a dithiol compound while simultaneously controlling the direction of their easy axis by an external magnetic field. Thus-obtained arrays showed anisotropic magnetic properties, revealing that the easy axis of L10-FePt nanoparticles fixed on the Si substrates has a preferred orientation perpendicular to the substrate surface. We also demonstrated that patterned arrays of the oriented L10-FePt nanoparticles can be fabricated by this method.