Fractional quantum Hall states in an optical lattice, Projekt OptimAL

Abstract

The interplay between magnetic fields and strongly interacting particles can lead to exotic phases of matter that exhibit topological order, such as fractional quantum Hall states. These phases were discovered in a solid-state setting, yet many of their properties remain unresolved. It has been proposed that topological matter may be created with neutral atoms by engineering synthetic magnetic fields. However, so far these experiments have mostly explored the weakly interacting regime, which precludes access to correlated many-body states.

We report on the generation of strongly correlated states of bosons in a synthetic magnetic field. We use a bottom-up strategy based on quantum state engineering in the interacting Harper-Hofstadter model: starting from an unentangled state with two particles, we ramp the system’s parameters to adiabatically connect the initial state with the target state. This allows us to reach and characterize quantum states at different filling factors, and to observe the transition from topologically trivial states to Laughlin-type fractional quantum Hall states. Our results mark the starting point for the exploration of strongly correlated topological matter with ultracold atoms.