Tailoring magnetic anisotropy and optical characteristics of nanostructural Co films by oblique angle deposition

Thin Co films on inclined Si(001) substrates were obtained by electron-beam evaporation. It has been established that at angles of incidence of the evaporated material on the substrate of more than 80$^\circ$ (oblique angle deposition), arrays of free-standing Co nanocolumns with a cross section of 25 nm and an aspect ratio (length/transverse size) of at least 15 are formed on the substrate surface. In this case, the magnetic easy axis of the film is oriented along the axis of the nanocolumns, which leads to the appearance of a normal component of the magnetization vector to the film surface. When the substrate rotation is turned on, an array of nanospirals is formed. With a fast rotation of the substrate (30 rpm), the magnetic easy axis approaches the normal to the film surface. At a slow substrate rotation (0.6 pm), an array of nanocoils is formed, imparting pronounced chiral properties to the film.