Assembly of Magnetic Nanoclusters*

Nanostructured Co or Fe-rich magnetic materials are of interest for a wide range of applications because of their novel structures and spin phenomena [1, 2]. In this presentation, the synthesis and stability of nanoparticles of (Co-Fe):X alloys (X $=$ Hf, Sm, Si) having unusual crystal structures will be discussed. The nanoparticles are produced using a single step-process in a cluster-deposition system and are smaller than 10 nm with an rms standard deviation of $\sigma $/$d \le $ 0.15. In particular, Co-rich nanoparticles such as HfCo$_{\mathrm{7}}$ and SmCo$_{5}$ exhibit high magnetocrystalline anisotropies ($K_{1}$ \textgreater 10 Mergs/cm$^{3})$ and saturation magnetic polarizations ($J_{s}$ \textgreater 10 kG). The nanoscale effects on the magnetism including spin structure, magnetic polarization, and other intrinsic properties, and the potential of the nanostructures for various applications will be presented. \\[4pt] [1] B. Balamurugan, B. Das, V.R. Shah, R. Skomski, X.Z. Li, and D.J. Sellmyer, \textit{Appl. Phys. Lett.} 101, 122407 (2012).\\[0pt] [2] Advanced Magnetic Nanostructures, Eds. D.J. Sellmyer and R. Skomski. Springer: New York, 2001.