AC magnetic field-induced rotation in levitating magnetostrictive wire

The rotation of magnetostrictive wires under excitation of an alternating axial magnetic field is a phenomenon discovered few years ago. Previous results and a recent mechanical experiment indicate that the appearance of these rotations is related to the sample vibrations associated to magnetoelastic resonance. This surprising behavior is here experimentally reported in polycrystalline FeNi levitating wires. An introductory analysis considering the balance of gravitational, magnetic gradient, and eddy-current forces is additionally carried out.