Ferromagnetic Microwire Systems as a High-Gradient Magnetic Field Source for Magnetophoresis

The use of amorphous ferromagnetic microwires has potential for applications in biomedicine and biophysics. Microwire arrays create magnetic fields that are characterized by strong spatial gradients. A system of ferromagnetic microwires with magnetizations across the diameter may efficiently accumulate paramagnetic particles along the wire due to forced diffusion. For typical system parameters, the particles concentration at the wire surface increases more than twice for a characteristic time of 30 s.  A pair of closely spaced microwires with diametric magnetizations (referred to as a dipole pair) yields a unique potential landscape with a two-dimensional minimum. The possibility of levitation of diamagnetic particles just above the dipole pair array was numerically demonstrated.