Effective magnetic moment of magnetic multicore nanoparticles
Journal article, 2009
We carry out Monte Carlo simulations to study the effective magnetic moment mu(eff) in the low-field region of magnetic multicore nanoparticles. Transmission electron microscopy and scanning electron microscopy images show that these particles contain a number of magnetic nanocrystals (MNCs) randomly packed in a single cluster of total volume V(tot). We illustrate how the initial magnetic susceptibility chi(0) of magnetic multicore nanoparticles can be straightforward derived from mu(eff) computed at zero magnetic field. We observe that dipolar interactions between MNCs and polydispersity of the MNCs contribute to increase and to decrease mu(eff)/V(tot), respectively, while magnetic anisotropy of the MNCs does not show any effect. In all three cases, mu(eff)/V(tot) can be described by a linear relation to (mu B/k(B)T)(2) that we analytically derived for low applied fields.
exchange interactions (electron)
nanoparticles
Monte Carlo methods
transmission electron microscopy
scanning electron microscopy
magnetic anisotropy
magnetic moments
magnetic susceptibility
Author
Vincent Schaller
Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory
Göran Wahnström
Chalmers, Applied Physics, Materials and Surface Theory
Anke Sanz-Velasco
Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory
Stefan Gustafsson
Chalmers, Applied Physics, Microscopy and Microanalysis
SuMo Biomaterials
Eva Olsson
Chalmers, Applied Physics, Microscopy and Microanalysis
Peter Enoksson
Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory
Christer Johansson
Physical Review B - Condensed Matter and Materials Physics
1098-0121 (ISSN)
Vol. 80 9 092406-Subject Categories (SSIF 2011)
Other Physics Topics
Condensed Matter Physics
Areas of Advance
Materials Science
DOI
10.1103/PhysRevB.80.092406