IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Magnetic Interfaces and Nanostructures Monday Sessions
       Session MI+NS-MoA

Paper MI+NS-MoA5
Self-assembled Magnetic Dots / Antidots and Dot Chains: Epitaxial Co/Ru(0001)@footnote *@

Monday, October 29, 2001, 3:20 pm, Room 110

Session: Nano Magnetics
Presenter: D. Li, Argonne National Laboratory
Authors: D. Li, Argonne National Laboratory
C. Yu, Argonne National Laboratory
J. Pearson, Argonne National Laboratory
S.D. Bader, Argonne National Laboratory
Correspondent: Click to Email
We have grown ~ 0-420 nm thick epitaxial Co wedges on flat and grooved Ru(0001) with molecular beam epitaxy at 350 °C to investigate self-assembly in metals and their magnetic properties utilizing ex-situ atomic force microscopy and magnetic force microscope. Three-dimensional islands (dots) or a flat film network with deep holes (antidots) in well-defined truncated pyramidal shapes appear below or above ~ 20 nm, respectively.@footnote 1@ The lateral sizes of these dots/antidots, as well as their spatial distribution on the flat substrates, tend to be uniform at a lengthscale of ~ 10@super 2@ nm in diameter and ~ 10@super 0@ nm in height. This growth mode is mainly driven by strain as a result of an 8% lateral mismatch between the basil plane lattice constants of bulk Co and Ru. On grooved Ru substrates, these self-assembled Co dots align into linear chains along the top and bottom of the grooves. The average dot-to-dot distance within a chain changes from ~ 500 nm to connecting into uniform stripes as a function of coverage. Magnetically, the dots are single domain with in-plane anisotropy. The dot chains have uniaxial anisotropy along the grooves and exhibit dipolar ferromagnetic inter-dot interaction. @FootnoteText@ @footnote *@ Supported by DOE BES-MS #W-31-109-ENG-38. @footnote 1@ Chentao Yu, Dongqi Li, J. Pearson, and S.D. Bader, Appl. Phys. Lett. 78, 1228 (2001).