Magnetoviscous and viscoelastic effects in ferrofluids

Suspensions of magnetic nanoparticles, commonly called ferrofluids, exhibit a broad variety of viscous effects induced by the action of magnetic field s. The related phenomena are in focus of research since about 30 years and have recently reached new dynamics due to the discovery of viscoelastic eff ects induced by magnetic fields. Here, effects due to the influence of magn etic fields on the rotation of single magnetic nanoparticles as well as coo perative phenomena and their importance for viscous effects in ferrofluids will be reviewed.