Self-persistent currents in coherent magnetic rings

It is shown that when a magnetic ring is cooled below its coherent temperature, with coherent length larger than the ring one, a perfectly measured non-negligible persistent current appears when the magnetization sets perpendicular to the plane of the ring, that is to say in the case of perpendicular magnetic anisotropy. This may happen in strained thin layer of magnetic metals and semiconductors. In particular, an application for a possible experiment in Ni thin films and Ni/Cu trilayers, showing perpendicular magnetic anisotropy, is discussed where magnetic fluxes of several quantum units can be reached that should lead to nA currents