Dresden 2009 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 4: Surface Magnetism I
MA 4.8: Vortrag
Montag, 23. März 2009, 12:45–13:00, HSZ 403
Comparing magnetic properties of Co adatoms measured with X-ray magnetic dichroism and spin excitation spectroscopy — •M. Etzkorn1, C. Hirjibehedin2, A. Lehnert1, S. Stepanow3, S. Ouazi1, C. Tieg4, P. Thakur4, S. Rusponi1, P. Gambardella3, A. Heinrich5, and H. Brune1 — 1Institut de Physique des Nanostructures, EPF-Lausanne, Switzerland — 2London Centre for Nanotechnology, UCL, United Kingdom — 3ICREA and Catalan Institut of Nanotechnology, Barcelona, Spain — 4ESRF, Grenoble, France — 5IBM Research Center, San Jose, USA
Spin excitation spectroscopy offers a new approach to determine the magnetic moment and anisotropy of single adatoms and atomic chains with a scanning tunneling microscope [1]. In order to compare these results with established methods we have started a series of X-ray circular magnetic dichroism (XMCD) measurements on one of the systems investigated with STM, namely Co-monomers on Cu2N/Cu(100). The XMCD spectra show that the Co is electronically largely decoupled from the Cu-substrate by the Cu2N-layer in agreement with the STS data. The X-ray adsorption spectra reveal that the electronic state of the Co on this surface has a predominant d8-character while the STS studies indicate a d7-state. On one hand the XMCD spectra clearly show a large orbital moment of the Co while the STS analysis has been performed in terms of an effective spin moment only. On the other hand the anisotropy determined by STS is in very good agreement with the angular dependance of the magnetic moment measured by XMCD. [1] A. Otte et al., Nature Physics 4 (2008) 847.