Orientation fluctuations in magnetotactic swimming

Abstract

The fluctuations experienced by magnetic microswimmers in a magnetic field often have non-thermal contributions, in particular in the case of biological swimmers such as magnetotactic bacteria. Here we study a model for an active self-propelled particle subject to correlated internal noise as a model for the active, non-thermal noise contribution and determine the effect of the correlation time on the diffusion of the swimmer and on its orientation in a magnetic field. A description in terms of an effective temperature is possible, but has limitations.