Alignment of self-assembled magnetic nanostructures: Co dot chains and stripes on grooved Ru(0001)

Abstract

We have deposited 0–60 nm Co with a wedge-shaped thickness gradient onto a grooved Ru(0001) substrate by means of molecular-beam epitaxy at 350 °C. The resultant epitaxial Co island (dot) structure was characterized ex situ using atomic- and magnetic-force microscopy and the magneto-optic Kerr effect. The dots self-assemble with ∼70–500 nm diameter, ∼1–7 nm height, and align into linear chains along the grooves with spacings in the chains to decrease from ∼1 μm until they form continuous stripes, depending on dosage and groove structure. The dots have magnetic single domains with in-plane easy axes.