Eur. Phys. J. Special Topics 187, 15-20 (2010)
https://doi.org/10.1140/epjst/e2010-01266-3

Regular Article

Anisotropic diffusion of a magnetically torqued ellipsoidal microparticle

¹ Departament de Química Física, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
² Institut de Nanociéncia i Nanotecnologia IN2UB, Universitat de Barcelona, Barcelona, Spain

^a e-mail: ptierno@ub.edu

Received: 3 August 2010
Revised: 9 August 2010
Published online: 1 October 2010

Abstract

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.