Permanent Magnet Levitation Stabilized by Diamagnetic Materials: A case-study

Earnshaw's theorem prohibits stable static levitation of permanent magnets in stationary fields with no energy input. However, by a proper placement of a diamagnetic material, the levitation is stabilized and two distinct suspension arrays (vertical and radial) are obtained. This compact implementations works without superconductors and may require no energy input. For the vertical stabilized configuration, this paper establishes the equilibrium and stability condition using an analytical procedure of magnetic field computation. An experimental model based on strong permanent magnets (NdFeB) and pyrolytic graphite validates these analytical results.