Seminar Prof. Dr. Arthura Ernsta iz Johannes Kepler Universität Linz, Max-Planck-Institut für Mikrostrukturphysik Halle pod nazivom “Exchange interaction in magnetic topological insulators and related materials” će se održati u četvrtak 5. srpnja 2018. godine na Prirodoslovno-matematičkom fakultetu Sveučilišta u Splitu, Ulica R. Boškovića 33, u dvorani B-3-47 s početkom u 10:00h.
Prof. dr. Arthur Ernst je suvoditelj bilateralnog hrvatsko-austrijskog projekta “Spin-orbit vezanje u mnogočestičnim sustavima” s višegodišnjim iskustvom istraživanja magnetskih topoloških izolatora i sličnih materijala.
Abstact: 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 magneto-electric 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 first-principles 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 electron-magnon 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.