Welcome to the Lise Meitner Research Group non-Hermitian topological phenomena
In our Lise Meitner Research Group “Non-Hermitian Topological Phenomena”, we study the topological features of non-Hermitian systems. While most theoretical research focusses on studying systems isolated from their surroundings, we take a more realistic perspective by taking environmental effects such as gain and loss of energy explicitly into account. As a consequence, we arrive at so-called non-Hermitian descriptions. This approach is highly relevant to quantum optics, electronics, mechanical metamaterials, nonconservative biological systems as well as quantum systems, to name a few. In recent years, non-Hermiticity has been investigated in the context of topology, which is a branch of mathematics describing properties that can only change step-wise and which has found many applications in physics. Adding the ingredients of non-Hermitian approaches and topology together has revealed a dramatic enrichment of the phenomenology of topological phases and resulted in a new, rapidly expanding cross-disciplinary research field. In our theory group, we focus on unraveling new trends of non-Hermitian topology in open and correlated quantum systems. We not only develop new theories and approaches but also actively collaborate with experimental partners. Our research is supported through the Lise Meitner Excellence Program 2.0 of the Max Planck Society as well as the ERC Starting Grant “NTopQuant”.
Exceptional non-Hermitian topology
Non-Hermiticity plays a central role in both classical and quantum systems. Classically, this arises, for example, from gain and loss processes in optics, while in the quantum realm, non-Hermiticity describes both the dynamics of open quantum systems and, scattering and decay due to phenomena such as interactions and disorder. Investigating non-Hermiticity through the lens of topology has resulted in the new exciting research field of non-Hermitian topology, as described in this review paper. Research in this area has so far mostly focussed on the classical domain. However, the goal of our group is to study non-Hermitian topology in open and correlated quantum systems. To that end, our multidisciplinary research program focusses on four main areas: higher-order exceptional points and symmetries, open quantum systems, strongly correlated systems, and (non)linear optical systems. In the context of the last of these, we actively collaborate with experimental groups at the institute, focusing on various optical platforms.
Our Team
Contact
Lise Meitner Research Group Flore Kunst
Max Planck Institute for the Science of Light
Staudtstr. 2
91058 Erlangen, Germany
Research group leader Dr. Flore Kunst
"We look at open and correlated quantum systems through a new lens with the aim to expand fundamental science as well as to work towards new applications."
