Vortex Core Dynamics.

The group of Prof. Mathias Kläui (LNSC - Laboratory of Nanomagnetism and Spin Dynamics) used a pump-probe photoemission electron microscopy technique to image the displacement of vortex cores in Permalloy discs due to the spin-torque effect during current pulse injection. Exploiting the distinctly different symmetries of the spin torques and the Oersted-field torque with respect to the vortex spin structure they determined the torques unambiguously, and quantified the amplitude of the strongly debated nonadiabatic spin torque. The paper was selected as an editor's choice and highlighted by a Viewpoint article (Physics 3, 91 (2010)).

L. Heyne et al., PRL 105, 187203 DOI: 10.1103/PhysRevLett.105.187203 (2010)