Onset of perpendicular magnetization in nanostripe arrays of Fe on stepped W(110) surfaces

Nanostripe arrays of alternating double layer and monolayer stripes of Fe(110) films were grown on stepped W(110) surfaces. The magnetic easy axis in the as-prepared samples switches from in-plane in the monolayer to perpendicular in the double layer stripes. Beyond a critical width, which is determined by exchange interactions, the double layer stripes show remanent perpendicular order. Magnetostatic interactions induce antiferromagnetic interstripe coupling, which suppresses perpendicular remanence at higher coverages. During residual gas exposure, the double layer easy axis is rotated into the plane, resulting in a sharp transition from antiferromagnetic to ferromagnetic interstripe coupling. [S0163-1829(99)01705-1].