The invention concerns a thin-layered magnetic device comprising, on a substrate, a composite assembly deposited by cathode spraying and composed of a magnetic layer (2) made from a material having high perpendicular magnetic anisotropy, the magnetization of which, in the absence of any electrical or magnetic interaction, is located outside the plane of said layer, a magnetic layer (3) in direct contact with the preceding magnetic layer (2), made from a ferromagnetic material with a high spin polarization rate, the magnetization of which, in the absence of any electrical or magnetic interaction, is located inside the plane of this layer, the direct magnetic coupling of this layer with said magnetic layer (2) inducing a reduction in the effective demagnetizing field of the assembly composed of the two magnetic layers (2) and (3), and a nonmagnetic layer (4) in direct contact with the preceding magnetic layer (3), made from a material that is non-depolarizing for the electrons passing through the device. The device includes means for passing an electric current through itself, in a direction substantially perpendicular to the plane of the layers.