Effect of dipolar interaction observed in iron-based nanoparticles

VARGAS, J.; NUNES, W. C.; SOCOLOVSKY, L. M.; KNOBEL, M.; ZANCHET, D.

Physical Review B - Condensed Matter and Materials Physics

American Physical Society

Año: 2005 vol. 1844 p. 1 - 1

0163-1829

Spherical magnetic nanoparticles with narrow size distribution and organic capping were diluted in paraffinwith different concentrations to verify the role of dipolar interactions on the macroscopic magnetic behavior.Increasing concentration of magnetic nanoparticles leads to higher blocking temperatures. The experimentaldata were analyzed by means of a recently proposed model that takes into account magnetic interactions ofdipolar origin, and an excellent agreement was found. Considering the magnetic interaction among particles itwas possible to obtain the real magnetic moment and estimate structural parameters that are consistent with theones obtained by small angle x-ray scattering and transmission electron microscopy.