On-line SPICE-SPIN+X Seminars
On-line Seminar: 14.12.2022 - 15:00 German Time
Skyrmions in chiral magnetic multilayers
Christopher Marrows, University of Leeds
Magnetic skyrmions are topologically-nontrivial spin textures with particle-like properties [1]. Their size, topological stability, and mobility suggest their use in future generations of spintronic devices, the prototype of which is the skyrmion racetrack [2]. To realise a racetrack requires three basic operations: the nucleation (writing), propagation (manipulation), and detection (reading) of a skyrmion, all by electrical means. Here we show that all three are experimental feasible at room temperature in Pt/Co/Ir or Pt/CoB/Ir multilayers in which the different heavy metals above and below the magnetic layer break inversion symmetry and induce chirality by means of the Dzyaloshinskii-Moriya interaction, defining the structure of Néel skyrmion spin textures [3]. We show deterministic nucleation on nanosecond timescales using an electrical point contact on top of the multilayer [4] (Figure 1), current-driven propagation along a wire in which the skyrmions are channelled by defects in the multilayer [5], and their detection by means of the Hall effect (Figure 2) that reveals an unexpectedly large contribution to the Hall signal that correlates with the topological winding number [6].
[1] N. Nagaosa & Y. Tokura, Nat. Nanotech. 8, 899 (2013)[2] A. Fert et al. Nature Nanotech. 8, 152 (2013)
[3] K. Zeissler et al. Sci. Rep. 7, 15125 (2017)
[4] S. Finizio et al., Nano Lett. 19, 7246 (2019)
[5] K. Zeissler et al., Nature Comm. 11, 428 (2020)
[6] K. Zeissler et al. Nature Nanotech. 13, 1161 (2018)
Please sign up here in order to get the Zoom link and regular announcements of the upcoming talks.
PDF file of the talk available here