Project B7
Colloids in Crossed Electric and Magnetic Fields
Project leaders
Summary
Whereas electric fields exert weak forces on both magnetic and non-magnetic colloids, magnetic fields act strongly and exclusively on magnetic colloids. We will make use of this difference to probe particle interactions in colloidal suspensions in an electric bottle, selectively addressing one particle species in a binary colloid mixture. The superposition of a second, either electrostatic or magnetostatic, field in parallel or normal direction allows to manipulate the motion of the charged/magnetic probe colloids within the "bath". Increasing the volume fraction of the probe particles, or modifying the superimposed field while a structure is assembling will further elucidate the role of dipolar interaction, dielectrophoretic/electrophoretic forces, and field-induced non-linearities in structure formation and dynamics.