The experimental realization of fractional quantum Hall states requires advanced methods both for providing the microscopic access to all particles of the quantum many-body system and for creating the artificial magnetic field that gives rise to these correlated states. The project ANYON has made important progress in these two issues.
Firstly, we have teamed up with another experimental group of our institute to develop a new microscopy technique, which we call quantum gas magnifier, and which is based on matter-wave magnification of the system before the optical imaging. This approach removes issues of depth of focus and of optical density and allows imaging three-dimensional systems with sub-lattice-resolution. By combining it with free-space fluorescence imaging for single-atom sensitivity, we will in the future use this method for imaging the fractional quantum Hall states and extract all relevant correlation functions. Furthermore, we have introduced a phase microscope, which allows to measure phases instead of densities with very high resolution, and employed it for studying the phase coherence in the topological BKT phase.
Secondly, we have worked towards the realization of artificial magnetic fields via a rotation of the trap making use of the formal equivalence of centrifugal and Lorentz force. We have produced such traps with high quality as optical tweezers shaped via digital mirror devices.
We have also teamed up with a theory group from ICFO to study the adiabatic preparation of the relevant states by appropriate sweeps of the trap rotation frequency and anisotropy and found protocols, which allow a tenfold speedup of the preparation time, making it easier to compete with heating from technical noise sources.
We have disseminated the results via presentations at many international conferences and workshops.
