Research

The magnetic anisotropy on three atomic layers thick islands of Co on Ru(0001) are studied by spin-polarized low-energy electron microscopy (SPLEEM) finding a change of two orders of magnitude with the change from fcc to hcp..

We have determined the origin of the magnetic anisotropy between 2D systems of Co layers three atoms thick which differ only in the stacking of the third layer. Islands with different stacking sequences present markedly different magnetic domain wall widths, while their shape, size and strain state are identical. The experimental observations allow the estimation of the effective in-plane magnetocrystalline anisotropy for each stacking sequence, which is of the order of 1.96 × 104 J m−3 for the fcc one and 2.5 × 102 J m−3 for the hcp one. The latter case is very close to the experimental realization of a 2D system with hexagonal symmetry which should have no in-plane anisotropy in a large temperature range.

Sandra Ruiz-Gómez, Lucas Pérez, Arantzazu Mascaraque, Benito Santos, Farid El Gabaly, Andreas K. Schmid and Juan de la Figuera, Nanoscale (2023) DOI:10.1039/d3nr00348e
https://pubs.rsc.org/en/content/articlepdf/2023/NR/D3NR00348E