  Optically-induced magnetic resonances in non-magnetic media have unlocked
magnetic light-matter interactions and led to new technologies in many research
fields. Previous proposals for the levitation of nanoscale particles without
structured illumination have worked on the basis of epsilon-near-zero surfaces
or anisotropic materials but these carry with them significant fabrication
difficulties. We report the optical levitation of a magnetic dipole over a wide
range of realistic materials, including bulk metals, thereby relieving these
difficulties. The repulsion is independent of surface losses and we propose an
experiment to detect this force which consists of a core-shell nanoparticle,
exhibiting a magnetic resonance, in close proximity to a gold substrate under
plane wave illumination. We anticipate the use of this phenomenon in new
nanomechanical devices.
