Topological materials are promising for future (opto-)electronic circuits, since computing schemes can be envisaged where the information carrying state is protected by topology.
Van der Waals materials and their heterostructure are an ideal platform to engineer and explore topological states. We can control and break the relevant symmetries of the Hamiltonian at will by interfacing different van der Waals materials with different symmetries. Furthermore, we can directly address the symmetry of the electron-Bloch states in the van der Waals crystal by external electric field in atomic field effect structures.
In turn, a wide range of non-trivial, i.e. topological quantum phenomena can be explored, such as the orbital Edelstein effect, Berry plasmons or even the interplay of plasmons and fringe states in quantum spin Hall-systems. Monolayers of Weyl semi-metals, such as WTe2, also have a superconducting phase far from charge neutrality. As a result, exotic phenomena such as Higgs and Majorana modes seem to be possible in the near future in such topological atomistic materials and field-effect heterostructures.
For our research, we gratefully acknowledge funding by the DFG via Grant KA 5418/1-1 within DFG Priority program 2244 " 2D Materials – Physics van der Waals [hetero]structures".
Furthermore, we acknowledge funding via TUM International Graduate School of Science and Engineering (IGSSE) and the Bavaria California Technology Center (BaCaTeC).
We are currently looking for MSc students to join research projects
in the group for 2022. Interested students are welcome to contact Christoph Kastl
to discuss specific projects.