Berlin 2005 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
MA: Magnetismus
MA 23: Spinabh
ängiger Transport III
MA 23.1: Vortrag
Dienstag, 8. März 2005, 10:30–10:45, TU H1028
Direct observation of current induced domain wall motion and wall spin structure modification — •Mathias Kläui1, Ulrich Rüdiger1, Pierre-Olivier Jubert2, Rolf Allenspach2, Laurent Vila3, Giancarlo Faini3, C.A.F. Vaz4 und J.A.C. Bland4 — 1FB Physik, Universität Konstanz — 2IBM Zürich Laboratory, Rüschlikon, Switzerland — 3LPN-CNRS, Marcoussis, France — 4Cavendish Laboratory, University of Cambridge, UK
Novel approaches to the switching of magnetic nanostructures are currently heavily investigated. A promising approach is switching by current-induced domain wall propagation (CIDP), where due to a spin torque effect, electrons transfer angular momentum to a head-to-head domain wall and thereby push it in the direction of the electron flow [1,2]. Here we use Spin-SEM to directly observe domain wall propagation in-situ in permalloy nanostructures induced by current pulses. We determine the propagation distances as a function of pulse height and pulse length for different types of domain walls (vortex, transverse). High resolution imaging allows us to image the nanoscale spin structure of the walls after and during the injection of currents and we observe that the current modifies the spin structure dramatically. Theoretically there are different competing approaches for incorporating spin torque effects into micromagnetic calculations [3,4] and direct comparison with our results allow us to discriminate between these theories. [1] M. Kläui et al., Appl. Phys. Lett. 83, 105 (2003) [2] A. Yamaguchi et al., Phys. Rev. Lett. 92, 77205 (2004) [3] A. Thiaville et al., J. Appl. Phys. 95, 7049 (2004) [4] S. Zhang and Z. Li, cond-mat/0407174 (2004)