Monika Aidelsburger
Floquet topological phases with ultracold atoms under the microscope


Date & heure
22/05/2024 – 11am
Lieu
Amphi Budé – Collège de France – 11 Place Marcelin Berthelot – 75005
Accueil
A coffee will be offered starting at 10:45 am, the seminar will start at 11am
Topological phases of matter can be generated in cold-atom systems using periodic driving, also known as Floquet engineering. While conventional topological insulators exhibit exotic gapless edge or surface states, as a result of nontrivial bulk topological properties. In periodically-driven systems the bulk-boundary correspondence is fundamentally modified and knowledge about conventional bulk topological invariants is insufficient. While ultracold atoms provide excellent settings for clean realizations of Floquet protocols, the observation of real-space edge modes has so far remained elusive. Here, I report on recent results, where we have demonstrated an experimental protocol for realizing chiral edge modes in optical lattices, by creating a topological interface in the form of a potential step using a programmable optical potential. We efficiently prepared particles in chiral edge modes in three distinct Floquet topological regimes that are realized in a periodically-driven honeycomb lattice. Moreover, the properties of the edge mode can be modified by controlling the height and sharpness of the potential step. In addition, I will present preliminary results on the interplay between disorder and topology and show how quantum gas microscopy can be used to measure observables that go beyond the detection of on-site occupations, such as local currents which is indispensable for detecting complex topological many-body states with equilibrium currents, such as strongly-interacting Meissner-like phases in optical ladders with artificial magnetic flux.
Michael Tarbutt
Centre for Cold Matter, Imperial College London
Searching for new physics with ultracold molecules
Ignacio Cirac
Max Planck Institute of Quantum Optics
Quantum Computing and Simulation in the presence of errors