Measuring the magnetization of three monolayer thick Co islands and films by x-ray dichroism

A. Mascaraque,A. K. Schmid,J. de la Figuera,J. F. Marco,L. Aballe,T. O. Menteş,F. El Gabaly,C. Klein,K. F. McCarty,A. Locatelli

doi:10.1103/physrevb.80.172401

Abstract

Co islands and films are characterized by x-ray magnetic circular dichroism photoemission electron microscopy. The spatial resolution capabilities of the technique together with atomic growth control permit obtaining perfectly flat triangular islands with a given thickness (3 ML), very close to an abrupt spin-reorientation transition. The magnetic domain configurations are found to depend on island size: while small islands can be magnetized in a single-domain state, larger islands show more complex patterns. Furthermore, the magnetization pattern of the larger islands presents a common chirality. By means of dichroic spectromicroscopy at the $\text{Co}\text{ }L$ absorption edges, an experimental estimate of the ratio of the spin and orbital magnetic moment for three monolayer thick films is obtained.

Highlights

Co islands and films are characterized by x-ray magnetic circular dichroism photoemission electron microscopy
The magnetic domain configurations are found to depend on island size: while small islands can be magnetized in a single-domain state, larger islands show more complex patterns
Co/Ru0001͒ has been the subject of many studies, ranging from multilayers to nanoparticles.3–14. In spite of this focused interest, only recently the presence of abrupt spin reorientation transitions in ultrathin Co/Ru0001͒ films has been reported:13,14 while in one atomic monolayerMLthick films the orientation of the remanent magnetization is parallel to the surfacei.e., the magnetic easy axis is in the film plane, films two layers thick show an out-of-plane magnetizationperpendicular magnetic anisotropy, ͑Ref. 15͔͒

Summary

Introduction

Co islands and films are characterized by x-ray magnetic circular dichroism photoemission electron microscopy. The magnetization pattern of the larger islands presents a common chirality.

Results

Conclusion