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Nanostrukturen und Grenzflächen Poster: Do., 13:00–15:30 D-P289
Magnetic and structural properties of deposited 3d transition metal nanoparticles
Armin Kleibert 1 , Johannes Passig 1 , Karl-Heinz Meiwes-Broer 1 , Joachim
Bansmann 2 , Renate K. Gebhardt 3 , Furkan Bulut 3 , Mathias Getzlaff 3
1 Institut für Physik, Universität Rostock, D-18051 Rostock, Germany – 2 Abt.
Oberflächenchemie und Katalyse, Universität Ulm, D-89069 Ulm, Germany – 3 Institut
für Angewandte Physik, Universität Düsseldorf, D-40225 Germany
Free clusters and nanoparticles are not just small pieces of material with physical
properties nearly identical to the bulk. Their electronic, optical and magnetic properties
are clearly size-dependent with a non-linear behaviour between the two general
limits given by the atomic and the bulk-like behaviour [1]. In this contribution we
compare the magnetic properties of mass-filtered Fe, Co and FeCo nanoparticles being
deposited onto different epitaxially grown thin films. The crystallographic structure
and morphology of the particles have been determined independently by means of
electron diffraction and high resolution transmission electron microscopy (HRTEM),
respectively (cf. Fig. 1). The magnetic moments of the clusters have been measured
in situ via X-ray absorption spectroscopy (XAS) as well as magnetic circular dichroism
(XMCD) after deposition onto ferromagnetic films. Moreover we will discuss the
presence of self-saturation effects in the nanoparticle spectra (cf. Fig. 2).
[1] J. Bansmann et al., Surface Science Reports, 56 (2005) 189
Fig. 1: High resolution
transmission image of an iron
nanoparticle with a diamter of
about 12nm,
Fig. 2: Top: comparison of a nanoparticle
TEY spectra with a reference
spectrum. Bottom: simulated spectrum
confirming the presence of selfsaturation
effects.