Anisotropic diffusion of a magnetically torqued ellipsoidal microparticle

We study the dynamics of an overdamped paramagnetic ellipsoidal particle confined above a plane and subjected to an external rotating magnetic field. Without magnetic forcing, the Brownian ellipsoid exhibits a crossover from a short time anisotropic diffusion to a long time isotropic one. Application of an external static or rotating magnetic field enables controlling and varying the crossover time depending on the field frequency and amplitude. We combine analytical results and numerical simulations in order to explore the diffusive properties of the forced ellipsoid.