Actuation and tracking of a single magnetic particle on a chip

We present the defined actuation of a single magnetic particle on a crossbar array chip. Two orthogonal layers of parallel microwires are used to generate highly localized magnetic field gradients for particle trapping and movement. We introduce an analytical model to simulate the actuation of the particle, which is in precise agreement with the experimentally observed trajectory. The single-particle approach allows us to resolve subtle features of the induced magnetic field distribution. We demonstrate that the actuation strongly depends on the applied current sequence and introduce switching patterns for reliable control of an individual particle. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3673909]