Enhanced diffusion and non-Gaussian dynamics in driven magnetic nanoparticles

Abstract

We investigate the out-of-equilibrium dynamics of paramagnetic colloidal nanoparticles driven above a triangular lattice of cylindrical ferromagnetic domains. We use an external precessing magnetic field to create a dynamic energy landscape which propels the particles along complex trajectories, characterized by an alternation of periodic orbital motion (localization) and stochastic particle jumping between nearest domains. We show that this system is populated by localized particles as well as delocalized (transported) ones, and tune their relative fraction via the field cone angle. Our driven system presents enhanced diffusive dynamics and an emergent non-Gaussian behavior which can be explained by considering two coexisting dynamic transport modes.