Bibcode
Hernando, A.; Sampedro, B.; Garcia, M. A.; Marin, P.; Rivero, G.; Crespo, P.; Gonzalez, J. M.
Bibliographical reference
eprint arXiv:cond-mat/0605496
Advertised on:
5
2006
Citations
4
Refereed citations
4
Description
We report on the origin of ferromagnetic like behaviour observed for 2.4
nm size Pd nanoparticles. Localised magnetic moments on metallic
surfaces have been recently shown to induce orbital motion of the
itinerant electrons via spin-orbit coupling. As a result of this
coupling the magnetic anisotropy is enhanced and the surface magnetic
moments can be blocked up to above room temperature. Since Pd has been
customary treated as a paradigmatic itinerant system, localisation of
magnetic moments at its surfaces was not initially expected. However, it
is shown, through the experimental thermal dependence of both magnetic
susceptibility and Hall resistance, that magnetism of bulk Pd, is a
localised paramagnetism and, consequently, can give rise to permanent
magnetism at its surface. Such surface permanent magnetism is
experimentally observed only when the percentage of surface moments is
outstanding as is the case for nanoparticles.