Subproject T1

Ultracold Atoms in Dynamically Created Gauge Fields

Prof. Dr. André Eckardt

Floquet engineering, the coherent control of a quantum system by means of time-periodic driving, has recently been employed very successfully for the dynamic realization of artificial gauge fields (magnetic fields or spin-orbit coupling) and topological band  structures for charge-neutral atoms in optical lattices. In this project we will study possibilities to extend these schemes to interacting systems. The aim is to develop theoretical understanding and new concepts enabling the preparation, manipulation, and characterization of topological states of matter in optical lattices. This includes different directions of research:

The impact of weak interactions on topological band structures shall be studied in systems of spinful fermions; here we will also work on schemes for adiabatic state preparation and the dynamical (quench-based) detection of system properties. We will develop protocols for the coherent control of small systems that take advantage of the new possibility to create tailor-made potential landscapes with high spatial resolution in recently developed quantum-gas microscopes. In this context we will look also for possible ways and optimal conditions for stabilizing, preparing, and probing topologically ordered droplet states (like fractional Chern insulators) in strongly interacting bosonic systems. Also the intrinsic heating of many-body Floquet systems will be investigated as well as strategies to minimize/suppress it in realistic experiments. Finally, we will pursue an open-system approach for describing mixtures of different (bosonic or fermionic) atomic species, addressing i.a. the question under which conditions the environment given by a second species can be beneficial for the preparation and stabilization of target states in driven systems.

Group Website