Berlin 2015 – wissenschaftliches Programm

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MA: Fachverband Magnetismus

MA 1: Tutorial: Density Functional Theory: A computational path to interesting spin-textures and novel skyrmions

MA 1.3: Tutorium

Sonntag, 15. März 2015, 17:45–18:30, H 1012

Magneto-transport properties in spiralling spin textures — •Yuriy Mokrousov — Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany

Spin-dependent transport properties in chiral magnets are currently of great interest both experimentally and theoretically. In this respect the skyrmion lattices comprised of topologically non-trivial whirls of magnetization which are typically stabilized at small magnetic field in the vicinity of the magnetic transition temperature are particularly intensively studied in B20 compounds. The Hall signal measured in these systems contains two topology-driven contributions due to the topological Hall effect (THE) and the anomalous Hall effect (AHE). It can be shown that the THE and AHE are a consequence of the Berry phases which electrons pick up in real and reciprocal spaces, respectively, while the so-called mixed Berry phases due to coupled dynamics in real and reciprocal space would give rise to a magnetic interaction which favors the chirality of the magnetization and gives rise to the skyrmion lattice - the Dzyaloshinskii-Moriya interaction (DMI). In my talk I will show how first principles methods can be used to justify the validity of the Berry phase concepts, as well as estimate and understand the physics of transport properties and DMI in skyrmion phase of complex materials. Moreover, I will try to convey a point that advanced material-specific modelling is a unique tool, which can be used to explore the emergent field of magneto-transport in nanometer-scale non-collinear textures.