Dynamics of Magnetic Whirls in Chiral Magnets
Prof. Dr. Achim Rosch (Institute for Theoretical Physics, University of Cologne)

In chiral magnets and small magnetic fields generically lattices of magnetic whirls, so-called skyrmions, form. These skyrmions can be manipulated by very small current densities. In the talk I discuss theoretical aspects of the coupling of magnetism and current in these systems. The coupling of the electric currents to the magnetic structure is mostly governed by Berry phases picked up when the spin of the electrons adiabatically follows the magnetic textures. The effect of these Berry phases can be described by effective “emergent” electromagnetic fields. The topological quantization of the the skyrmions thereby leads to a quantization of the emergent flux, which also fixes the strength of the emergent electric fields when the skyrmions move.
I will also discuss how skyrmions can be created and destroyed in a process where the topology of the magnetic structure changes: this process is described by the dynamics of emergent magnetic monopoles.

All interested are cordially welcome! Organize your personal meeting with the lecturer by contacting M. Kläui