LIGHT-DIFFRACTION EFFECTS IN THE MAGNETOOPTICAL PROPERTIES OF 2D ARRAYS OF MAGNETIC DOTS OF AU/CO/AU(111) FILMS WITH PERPENDICULAR MAGNETIC-ANISOTROPY

Using X-ray lithography and ion beam etching we have patterned micrometer-sized square lattices of round dots, out of Au/Co/Au(111) films with perpendicular easy magnetization axes. The magneto-optical Kerr rotation shows strong variations versus the diffraction order, the light polarization direction and the ratio of film to background reflectance, particularly when the lattice spacing is high compared with the dot size. This reveals an important interplay between diffraction and magneto-optics.