Fabrication of core-shell type magnetic nanoparticles by a nanocluster deposition technique

Nanoparticle deposition gun and on-line co-sputtering technique was used to prepare core-shell type Au@Fe₆₅Co₃₅ nanostructures on glass substrates. The crystallization, texture and nanostructures were observed by using transmission electron microscopy (TEM), while the magnetic properties of the nanoparticles were measured by the use of a vibrating sample magnetometer. TEM observations including bright/dark images and diffraction patterns showed that all FeCo nanoparticles are single crystals and show random orientations. The hysteresis loop measured at room temperature has an average diameter of about 23 nm, and the coercivity is about 60 Oe. Au shell thickness is about 1-2 nm.