Trajectory shift of magnetic microchains in an oscillating field

Abstract

We report an interesting phenomenon of "trajectory shift" of magnetic chains in an oscillating field, when the phase angle lags of chains to the external field exceeding 90A degrees. The phenomenon shifts the oscillating trajectory of chain along a new axis, which is perpendicular to its original axis. Applicability of the phenomenon to a stable chain in various conditions is experimented systematically. The trajectory shift provides an effective manipulating mechanism in micro-electro-mechanical-systems, such as steering of micro-swimmers. We successfully demonstrate that the driven direction of a micro-swimmer can be controlled by shifting its oscillating trajectory without a physical re-configuration of the external field.