Magnetic Soft Matter in a Rotating Field

Abstract

An overview of soft matter behavior in a rotating magnetic field is given and the basic phenomena of single ferromagnetic and paramagnetic particles are described: synchronous and asynchronous regimes, structural instability leading to the precessional regime and others. Their applications in microrheology are discussed. As a particular example of an active magnetic system, magnetotactic bacteria are considered and several important phenomena, such as complex trajectories, synchronization, diffusion due to the internal noise are described. As an important application of these descriptions, hydrodynamics with spin is considered and the conditions for the transformation from microscopic rotational motion of the particles to the macroscopic motion of their suspension are described. Finally, exciting perspectives for further development of the field, such as hydrodynamics of systems with odd viscosity, are briefly discussed.