Würzburg ToCoTronics Colloquium
"Axion and antiferromagnetic topological insulators"
|12.05.2022, 16:15 - 18:00 Uhr
|SFB 1170 ToCoTronics
|David Vanderbilt - The State University of New Jersey
Topological materials have been a hot topic of research in the last decade, with much recent interest turning to the subject of magnetic topological insulators. Like their nonmagnetic cousins, these are typically characterized by a band inversion accompanied by strong spin-orbit coupling, but with the time-reversal symmetry spontaneously broken, some other symmetry, such as inversion, is required to protect the topology. A fascinating property of these "axion" or "antiferromagnetic topological" insulators is that their insulating surfaces automatically display a half-integer quantum anomalous Hall state, similar to the better known quantum Hall effect but at half strength and free of the need for any external magnetic field. After giving an introduction to the theory behind these effects, I will briefly review recent attempts to find experimental realizations of such materials. I will end by looking ahead to some exciting opportunities presented by such materials, especially the presence of one-way quantum wire states and their intersections that could potentially be engineered to occur on the surface.
This talk is broadcasted only via zoom. To enter the meeting, follow the link: