Abstract

Floquet driving of quantum gases in optical lattices, e.g., using periodically modulated forces or lattice potentials, offers versatile mechanisms for creating tailored lattice potentials in quantum simulation experiments. Recent achievements include the realization of artificial magnetic fields and topological lattice models. Simulating many-body states of interacting particles, however, remains challenging as interactions create instabilities and heating that quickly destroy the coherence of the system. I am going to discuss recent experiments [1-3] that study the role of interactions for the time evolution of superfluids in the lowest band of a driven lattice. Depending on system parameters such as driving strength, lattice depth and interaction strength, we identified stable and unstable parameter regions and provided a general resonance condition. In contrast to the high-frequency approximation of a Floquet description, we used the superfluid’s micromotion to analyse the growth of phonon modes from slow to fast driving frequencies. Our model allows us to identify several causes for Floquet heating and to develop strategies to avoid it.