17.10.2017  16:00, Raum: S288 
Prof. Dr. Arthur Ernst
(Johannes Kepler Universität Linz, Österreich)
Exchange interaction in magnetic topological insulators and related materials It is a well known fact that a magnetic field can break the time reversal symmetry and therewith can destroy a topologically protected surface state in topological insulators. However, the interplay between magnetism and topological order can yield a number of interesting phenomena such as the quantum anomalous Hall effect, a topological magnetoelectric effect, and quantised Kerr or Faraday rotation. This motivates researcher for a search of new magnetic topological insulators and for an intensive study of their electronic and magnetic properties. In my talk, I’ll give an overview of our firstprinciples investigations on this class of materials. In the first part, I’ll present a method and approximations used in our simulations and then talk about several examples of magnetic topological insulators, studied in our group within the last three years. First of all, I’ll discuss topological insulators doped with magnetic impurities, which can imply various magnetic order in these materials. A special attention will be devoted to the exchange interaction between magnetic impurities and to the impact of electronmagnon interaction on the electronic structure in some doped topological systems. As next, I’ll demonstrate how some defects or impurities without magnetic moments can induce magnetism in topological insulators and discuss the main features of magnetic interactions in these systems. 

21.11.2017  16:00, Raum: S288 
Dr. Axel Lubk
(IFW Dresden)
Advanced Holographic Tomography for 3D Magnetic Imaging in Magnetic Textures 

5.12.2017  16:00, Raum: S288 
Prof. Dr. Martino Poggio
(Department of Physics, University of Basel)
Nanomechanics and Nanomagnetism 

16.1.2018  16:00, Raum: S288 
Prof. Dr. Markus Grüninger
(II. Physikalisches Institut, Universität zu Köln)
RIXS on facesharing iridates: From j=1/2 to quasimolecular orbitals 