Condensed Matter Physics Seminar - Maria Hermanns

Science and Information Technology

This is part of a virtual seminar series in theoretical condensed matter and atomic physics, with the aim to connect researchers working at different Nordic universities.

13 Oct 2023
13:15 - 14:15
Online via zoom

Topological phases at criticality

Maria Hermanns (Stockholm University)

Abstract: One standard assumption for classifying topological phases of matter is that the system has an (at least partial) energy gap. More precisely, the corresponding topological invariants become generically ill-defined when the system becomes gapless, i.e. at critical points. Nevertheless, it was observed that certain hallmarks of topological phases, in particular the presence of robust edge modes, survive at criticality.  In this talk, we discuss two distinct ways of how to generalize topological invariants to systems without an energy gap, as well as their properties. We will also introduce a relation between critical hermitian and gapped non-hermitian phases, using the example of one-dimensional systems with chiral symmetry. 

The seminar is held digitally via Zoom


Read more about the seminar series

Condensed Matter Physics Seminar