A simulation approach for the finite-temperature magnetic properties, stochastic dynamics and heating properties of magnetic nanoparticles composed of FM core/AFM shell

Abstract

Using the Monte Carlo simulation method based on the Metropolis algorithm, we present some results regarding the magnetic and heating properties of three-dimensional nanoparticles composed of a ferromagnetic core surrounded by an antiferromagnetic shell. We investigate the variation of the exchange bias effect and its dependence on the particle shell thickness, as well as on the temperature. In terms of the stochastic dynamics, we applied a time-dependent alternating magnetic field on the system, and calculated the dynamic-order parameters, response functions and the hysteresis loop area from the AC hysteresis curves from which we have also quantified the specific absorption rate (SAR) of the particle over a wide range of field frequencies. A number of interesting results have been found regarding the variation of the heating properties of the system as a function of the antiferromagnetic shell thickness and the period of the alternating field.