Magnetism of ordered Sm/Co(0001) surface structures

TL;DR

This study investigates the magnetic properties of Sm/Co(0001) surface structures, revealing ordered phases and a significant increase in coercivity with 1 ML Sm, using advanced spectroscopic and magneto-optical techniques.

Contribution

It provides new insights into the magnetic behavior of Sm/Co(0001) surfaces, identifying ordered phases and their impact on coercivity enhancement.

Findings

Two ordered phases for 1/3 and 1 ML Sm were identified.

1 ML Sm significantly increases coercivity compared to pure Co films.

Element-specific hysteresis loops show similar magnetic behavior for Sm and Co.

Abstract

The epitaxial system Sm/Co(0001) was studied for Sm coverages up to 1 monolayer (ML) on top of ultrathin Co/W(110) epitaxial films. Two ordered phases were found for 1/3 and 1 ML Sm, respectively. The valence state of Sm was determined by means of photoemission and magnetic properties were measured by magneto-optical Kerr effect. We find that 1 ML Sm causes a strong increase of the coercivity with respect to that of the underlying 10 ML Co film. Element-specific hysteresis loops, measured by using resonant soft x-ray reflectivity, show the same magnetic behaviour for the two elements.