Dresden 2014 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 37: Spin Torque and Spin Excitations I
MA 37.2: Vortrag
Donnerstag, 3. April 2014, 09:45–10:00, HSZ 401
Tuning Spin Transfer Torques in Chiral Magnets — •Christoph Schnarr, Robert Ritz, Andreas Bauer, Christian Franz, and Christian Pfleiderer — Technische Universität München, Physik-Department E21, D-85748 Garching, Germany
Small angle neutron scattering and Hall effect measurements recently revealed sizeable effects of spin transfer torques in the skyrmion lattice phase of MnSi [1,2]. The associated critical current densities of ∼ 106 Am−2 are exceptionally small and about 5 orders of magnitude smaller than the spin transfer torques observed in conventional systems. The low critical current density is due to a very efficient gyromagnetic coupling due to the non-trivial topology of the skyrmion lattice, as well as combination of stiffness of the skyrmion lattice and collective pinning. We report spin transfer torque experiments, based on the Hall effect in chiral magnets for various tuning parameters, where the topological Hall effect increases by up to a factor of ten suggesting a large variation of the coupling of the electric currents to the magnetic structure. The dependence of jc on the tuning parameters will be discussed in view of the increased topological Hall effect as well as the increased pinning by disorder.
F. Jonietz et al., Science 330, 1648-1651 (2010)
T. Schulz et al., Nat Phys 8, 4, 301-304 (2012)