SEMINAR:New frontiers in topology in multi-level systems

Speaker: Nur Ünal, Cavendish Laboratory, University of Cambridge

Title: New frontiers in topology in multi-level systems 

Date/Time: 29 March 2023 / 13:40 - 14:30

Zoom Link:https://sabanciuniv.zoom.us/j/98580414849?pwd=UjFOb3h0TFUxbEg0UWp2cjVzUmM3Zz09

Passcode: 803101

Abstract: Topologically protected phases profit from connections with mathematical principles to characterize illustrious physical behaviors in tangible systems. State-of-the-art quantum simulators provide a versatile platform for exploring these phenomena at a fundamental level, even providing the opportunity for observing the ‘knots’ that wave functions tie during their evolution. Many of these topological evaluations are related to the underlying quantum geometry, for which the Bloch sphere constitutes a paradigmatic example in the minimal of two levels. In this talk, I will introduce a geometric description for N-level systems in terms of a nested structure comprising spheres, which opens up a new avenue for the interpretation of the topological classification and the dynamical illustration of multi-level systems as well as the design of new experimental probes. Furthermore, I will present new exotic topologies involving non-Abelian braiding of band nodes in multi-gap non-interacting systems. I will demonstrate new anomalous topological phases in out-of-equilibrium settings with no static counterparts as well as ways for quantum simulators to probe them.

References:

[1] Slager, Bouhon, Ünal, arXiv:2208.12824. 

[2] Kemp, Cooper, Ünal, Phys Rev Research 4, 023120 (2022).