Regensburg 2019 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
MA: Fachverband Magnetismus
MA 51: Magnetism Poster B
MA 51.50: Poster
Donnerstag, 4. April 2019, 15:00–18:00, Poster C
Field-induced anomalous Hall effect in 2D transition metal dichalcogenides — •Franz Fischer1, Nicki F. Hinsche1, and Ingrid Mertig1,2 — 1Martin Luther University Halle-Wittenberg , Institute of Physics, 06099 Halle/S., Germany — 2Max Planck Institute of Microstructure Physics, 06120 Halle/S., Germany
Atomically thin layers of transition metal dichalcogenides (TMDC) attract remarkable interest due to their extraordinary electronic and optical properties. Their inherent crystal structure lacks inversion symmetry and therefore enables an extra valley degree of freedom in addition to charge and spin. Combining heavy metal atoms and chalcogenes results in strong spin-orbit interaction. The latter gives rise to large spin splittings in the Brillouin zone (BZ), leading to presumably large Berry curvature in those valleys. A consequence of the momentum-locked Berry curvature is the valley Hall effect, which can be validated via photo-optical experiments.
We are extending these concepts by gaining access to a net Berry curvature in the BZ as we tune the electronic band structure via applying electrical and magnetic fields. The latter entails time and spatial symmetry breaking, that allows us to induce spin-polarized currents and the realization of an anomalous Hall effect (AHE). We report on theoretical calculations based on a tight-binding model, for several TMDCs, e.g. MoS2. In dependency on various parameters the evolution of the Berry curvature and with that the AHE is discussed. Our results will give a leap forward on new spin- and valleytronic devices incorporating TMDC/ferromagnet/ferroelectric interfaces.