Magnetic interaction of nanoclusters in a bimodal ferrocolloid

Abstract

The paper discusses the problem of interaction between a pair of superparamagnetic nanoclusters suspended in a nano-dispersed ferrocolloid and subjected to a uniform magnetic field. The main research instrument is the Langevin dynamics simulation method. Dipole-dipole and steric interactions between nanoparticles and clusters are directly taken into account. The net force acting on the clusters is calculated for various values of the controlling parameters – the intensity of the applied field and the energy of dipole-dipole interparticle interactions. In the wide ranges of these values, there is observed an effective short-range attraction between the clusters. The strength of the interaction increases with an increase in the dipolar coupling parameter. It has been established that the self-organization of nanoparticles in the vicinity of the clusters also enhances their attraction. Other conditions being equal, the force of intercluster attraction in a structured ferrocolloid can be 1.5–2 times higher than in a homogeneous one.