https://doi.org/10.1140/epjb/e20020084
Effect of positional disorder in systems of ultrafine ferromagnetic particles
Max-Planck-Institut für Physik komplexer Systeme,
Nöthnitzer Strasse 38, 01187 Dresden, Germany
Corresponding author: a porto@mpipks-dresden.mpg.de
Received:
28
November
2001
Published online: 15 March 2002
A simple model for systems of dipolarly interacting single-domain ultrafine ferromagnetic particles is studied by Monte Carlo simulations of zero field cooling and field cooling as well as relaxation experiments. By investigating systems characterized by an identical moderate concentration but different types of particle positions' disorder, it is shown that the positional disorder has a crucial influence on the magnetic behavior of the system. For extreme values of positional disorder, the interplay between spatial disorder and dipolar interaction can even lead to a cooperative freezing at low temperatures.
PACS: 75.50.Tt – Fine-particle systems; nanocrystalline materials / 75.40.Mg – Numerical simulation / 75.50.Lk – Spin glasses and other random magnets
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002