C Antoniak et al 2009 J. Phys.: Conf. Ser. 190 012118 doi:10.1088/1742-6596/190/1/012118
C Antoniak1, M Spasova1, A Trunova1, K Fauth2, M Farle1 and H Wende1
Show affiliationsThe influence of structural and compositional changes within FePt nanoparticles on their magnetic properties was studied by means of x-ray absorption spectroscopy in the near-edge regime and its associated magnetic circular dichroism as well as by analysis of the extended x-ray absorption fine structure. The magnetic moments at the Fe sites were found to be a sensitive monitor to changes of the local surrounding: While compositional inhomogeneities in the nanoparticles yield significantly reduced magnetic moments (by 20–30%) with respect to the corresponding bulk material, thermally induced changes in the crystal structure yields strongly enhanced orbital contributions (up to 9% of the spin magnetic moment). Also the break of crystal symmetry at the surface leads to an enhanced orbital magnetism which was confirmed by determination of the ratio of orbital-to-spin magnetic moment for FePt particles with different sizes between 3 and 6 nm in diameter.
75.30.Cr Saturation moments and magnetic susceptibilities
75.50.Tt Fine-particle systems; nanocrystalline materials
78.70.Dm X-ray absorption spectra
75.75.+a Magnetic properties of nanostructures
Issue 1 (2009)
C Antoniak et al 2009 J. Phys.: Conf. Ser. 190 012118
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