AVS 47th International Symposium
    Magnetic Interfaces and Nanostructures Thursday Sessions
       Session MI+NS+NANO 6-ThM

Paper MI+NS+NANO 6-ThM7
Correlation of Structural and Magnetic Properties of Ultra-Thin Fe-Films on W(110) by Spin-Polarized STM/STS

Thursday, October 5, 2000, 10:20 am, Room 206

Session: Nanomagnetism
Presenter: A. Kubetzka, University of Hamburg, Germany
Authors: A. Kubetzka, University of Hamburg, Germany
O. Pietzsch, University of Hamburg, Germany
M. Bode, University of Hamburg, Germany
R. Wiesendanger, University of Hamburg, Germany
Correspondent: Click to Email
To investigate magnetism at the nm-scale and to improve the understanding of its underlying principles, a magnetic imaging technique with ultra-high resolution is of vital importance. Recently, spin-polarized scanning tunneling microscopy/spectroscopy has been developed to a reliable tool to allow such investigations down to the atomic level.@footnote 1,2@ We investigated Fe-films on W(110) at T = 15 K in a coverage range of 1 to 2 ML. In this regime Fe grows as double layer islands interconnected by a closed ML, where the island size can be tuned by the amount of evaporated Fe. By using ferromagnetically coated tips with a magnetization direction along the tip axes, we are sensitive to the out-of-plane component of the sample magnetization. Our measurements reveal that above a critical width of about 2.5 nm along the [1-10] direction, the islands are magnetized perpendicularly to the film plane. Below this width we do not observe a magnetic contrast which we attribute to a reorientation of magnetization to in-plane. Whereas the small perpendicularly magnetized islands are in a single domain state, we observe domain walls above a coverage of 1.5 ML, with wall widths of w = 7±1 nm. @FootnoteText@ @footnote 1@ Pietzsch et al., Phys. Rev. Lett. 84, (2000). @footnote 2@ Heinze et al., Science (accepted).