Gustav Bihlmayer

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Topological insulators (TIs) are fascinating materials due to their protected
edge-states and their possibilities for spintronic applications. Spin-orbit
coupling and exchange effects at interfaces give us a possibility to tailor
the properties of two-dimensional (2D) topological materials. While magnetism
is usually detrimental to the topological properties, we show that exchange
interactions offer the possibility to realize a variety of new phases depending
on the structural symmetry and the direction of the magnetic (exchange) field.
Using density functional theory we explore the quantum spin Hall to quantum
anomalous Hall state transition in TIs and topological crystalline insulators.
We propose the existence of new states like mixed nodal-line semimetals or
mixed Weyl semimetals in the phase diagram of these 2D materials, showing
interesting magnetoelectric coupling phenomena as function of the magnetization
direction.

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FZ Jülich
Seminar Room of the Institute of Physics II
Contact: Alexander Grüneis