Monte Carlo Study of the Exchange Bias Effects in Magnetic Nanoparticles with Core–Shell Morphology

Abstract

Bi-magnetic nanoparticles (NPs) with core-shell morphology are gaining considerable interest both in research and technological applications. Nowadays, the technological demand for thermal stability of very small particles at room temperature, namely the increase in their blocking temperature, has led to the search of a great variety of bi-magnetic core-shell NPs, whose core and shell are consisted of a soft and a hard magnetic phase of either ferromagnetic, ferrimagnetic, antiferromagnetic, or even spin-glass like structure. The Monte Carlo (MC) simulation technique with the implementation of the Metropolis algorithm has been proved a very powerful tool for the systematic study of the magnetic behavior of NPs and NP assemblies at finite temperature. Modeling of the exchange bias behavior of core-shell NPs is a very challenging issue because of the variety of core-shell structures. The most common shape of core-shell bi-magnetic NPs is the spherical one.