Close-up of the magnetic head (3 pairs of coils), mounted around a microscope objective lens.Suspension of micrometer-sized super-paramagnetic micrometer beads. Initially, there is no external magnetic field and one observes Brownian motion only. At time t=3 s, weak magnetic field is applied in the vertical direction.Suspension of micrometer-sized super-paramagnetic micrometer beads sandwiched between two glass plates. Initially, there is no external magnetic field and one observes Brownian motion only. At time t=2 s, weak magnetic field is applied perpendicular to the particle plane.
