Join us for a seminar by Dr Nur Ünal of the Theory of Condensed Matter Group, University of Cambridge.
Out-of-Equilibrium Topology, Multi-level systems and non-Abelian singularities
Abstract: While initial studies on topologically protected phenomena have focused on regimes close to equilibrium to identify robust quantized responses, a plethora of possibilities has been unlocked far from equilibrium recently, forcing to extend known topological characterisations to out of equilibrium. In this talk, I will introduce new topological invariants arising under quantum quenches or periodic driving. Particularly, in multi-level systems, new exotic topologies have been predicted in recent years involving non-Abelian properties and braiding of band singularities. I will present observable signatures of these non-Abelian properties which are within reach of state-of-the-art quantum simulators and demonstrate specific interferometry schemes. Reaching beyond the non-Abelian band topology, many of these topological evaluations are related to the underlying quantum geometry where new structures emerge beyond minimal two-level models and the simple Bloch sphere picture. I will introduce new geometric descriptions in these higher dimensional spaces with potential applications.