Magnetocaloric effects in magnetic nanoparticle systems: A Monte Carlo study

A superparamagnetic nanoparticle system is a good candidate for implementing the magnetocaloric effect, due to its suitable properties as a frozen ferrofluid able to follow a thermodynamic cycle. For such aim, we have concentrated on the study of the entropy dependence on both the particle size and sample concentration using a Monte Carlo simulation. We have found that for a given sample concentration there exists a particle size for the larger entropy increase, and reciprocally for a given particle volume there exists a sample concentration able to produce the larger entropy change.