Newly developed millimeter-sized superconducting linear actuator with superconducting slider

A millimeter-sized superconducting linear actuator has been developed. The actuator consists of a superconducting slider, a stator, amplifiers, and a personal computer. Exciting currents for six-phase excitation are applied to the electromagnets of the stator. The experimental results show that the superconducting slider moves over the stator without any mechanical contacts and that the motion resembles a stepping motor. The stable position for the levitating slider depends on the magnetic field produced by the electromagnets. The maximum speed of the slider is more than 10 mm/s.