title: Enhanced orbital magnetism in Fe(50)Pt(50) nanoparticles.
abstract: X-ray absorption and magnetic circular dichroism spectra at both the Fe and Pt L(3,2) edges were measured on wet-chemically synthesized monodisperse Fe(50)Pt(50) particles with a mean diameter of 6.3 nm before and after complete removal of the organic ligands and the oxide shell covering the particles by soft hydrogen plasma resulting in a pure metallic state. After thermal treatment of the metallic particles, the coercive field increased by a factor of 6, the orbital magnetic moment at the Fe site increased by 330% and is reduced at the Pt site by 30%, while the effective spin moments did not change. A decrease of the frequency of oscillations in the extended x-ray absorption fine structure at the Pt L(3,2) edges provides evidence for crystallographic changes towards the L1(0) phase.
authors.affiliation: Experimentalphysik-AG Farle, Fachbereich Physik, Universität Duisburg-Essen, Lotharstrasse 1, 47048 Duisburg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Antoniak
authors.forename: J
authors.initials: J
authors.lastname: Lindner
authors.forename: M
authors.initials: M
authors.lastname: Spasova
authors.forename: D
authors.initials: D
authors.lastname: Sudfeld
authors.forename: M
authors.initials: M
authors.lastname: Acet
authors.forename: M
authors.initials: M
authors.lastname: Farle
authors.forename: K
authors.initials: K
authors.lastname: Fauth
authors.forename: U
authors.initials: U
authors.lastname: Wiedwald
authors.forename: H-G
authors.initials: HG
authors.lastname: Boyen
authors.forename: P
authors.initials: P
authors.lastname: Ziemann
authors.forename: F
authors.initials: F
authors.lastname: Wilhelm
authors.forename: A
authors.initials: A
authors.lastname: Rogalev
authors.forename: Shouheng
authors.initials: S
authors.lastname: Sun