By means of spin-polarized low-energy electron microscopy (SPLEEM) we show that the magnetic easy-axis of one to three atomic-layer thick cobalt films on ruthenium crystals changes its orientation twice during deposition: one-monolayer and three-monolayer thick films are magnetized in-plane, while two-monolayer films are magnetized out-of-plane, with a Curie temperature well above room temperature. Fully-relativistic calculations based on the Screened Korringa-Kohn-Rostoker (SKKR) method demonstrate that only for two-monolayer cobalt films the interplay between strain, surface and interface effects leads to perpendicular magnetization.
@article{arxiv.cond-mat/0512220,
title = {Imaging Spin Reorientation Transitions in Consecutive Atomic Co layers},
author = {Farid El Gabaly and Silvia Gallego and Carmen Munoz and Laszlo Szunyogh and Peter Weinberger and Christof Klein and Andreas K. Schmid and Kevin F. McCarty and Juan de la Figuera},
journal= {arXiv preprint arXiv:cond-mat/0512220},
year = {2007}
}
Comments
5 pages, 4 figures. Presented at the 2005 ECOSS conference in Berlin, and at the 2005 Fall meeting of the MRS. Accepted for publication at Phys. Rev. Lett., after minor changes