Berlin 2024 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 22: Focus Session: Young Semiconductor Forum
HL 22.12: Poster
Tuesday, March 19, 2024, 11:00–15:30, Poster F
Non-Hermitian Physics in multiterminal devices — Kyryl Ochkan1, Viktor Könye1, Louis Veyrat1, Anastasiia Chyzhykova1, Romain Giraud1, Dominique Mailly2, Antonella Cavanna2, Ulf Gennser2, Ewelina Hankiewicz1, Bernd Büchner1, Jeroen Van den Brink1, Jan Carl Budich1, Ion Cosma Fulga1, and •Joseph Dufouleur1 — 1Würzburg-Dresden Cluster of Excellence ct.qmat, Dresden, Germany — 2Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Saclay, Palaiseau, France
One of the simplest examples of non-Hermitian topology is encountered in the Hatano-Nelson (HN) model, a one-dimensional chain where the hopping in one direction is larger than in the opposite direction. We present here the first experimental observation of non-Hermitian topology in a quantum condensed-matter system made of a multi-terminal quantum Hall device etched in a high mobility GaAs/AlGaAs two-dimensional electron gas ring. In our device, we directly measure and evidence the non-Hermitian skin effect. We also compute for our experimental device two topological invariants that are found to be more robust than the Chern number. We finally use the unique properties of our system and continuously tune the system configuration between open and periodic boundary conditions [1]. We also present the latest developments with regard to the application to electronic devices that can be used as topological ohmmeters [2].
[1] K. Ochkan et al. (arXiv:2305.18674, Nature Physics - in press) [2] V. Könye, et al. (arXiv:2308.11367, under review)
Keywords: non-Hermitian Physics; Topology; Semiconducting heterostructures; Quantum Hall Effect; Topoelectronics