AG Mathematische Physik, Flore Kunst (Max Planck Institute for the Science of Light, Erlangen): Exceptional non-Hermitian topology

Flore Kunst (Max Planck Institute for the Science of Light, Erlangen

Exceptional non-Hermitian topology

Abstract: While topological phases of matter have predominantly been
studied for isolated Hermitian systems, a recent shift has been made
towards considering these phases in the context of non-Hermitian
Hamiltonians. Non-Hermitian topological phenomena reveal an enrichment
of the phenomenology of topological phases, and forms a rapidly growing
new cross-disciplinary field. In this talk, we will see that
non-Hermitian Hamiltonians, which come about due to, e.g., gain and
loss, feature many exotic properties, which are radically different from
their Hermitian counterparts. In particular, I will focus on our recent
work on higher-order exceptional points, which are truly non-Hermitian
degeneracies, the role played by symmetries and similarities, and
present explicit toy models to illustrate our findings. Additionally, I
will discuss the role of exceptional points in nonlinear Kerr resonators.

Abstract: