Programmable light potentials for studying edge states and quantum thermodynamics

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Ultracold atoms in optical lattices offer unique possibilities as quantum simulators for the study of many-body quantum systems, relevant for example to material science and other disciplines. To further enhance the capabilities of these systems, we use programmable static and dynamically varying light potentials - a technology that we developed in WP6 within the first years of the QCS Hub programme. Our approach uses a spatial light modulator to create arbitrary potentials which we can project onto the atoms with sub-wavelength resolution by our quantum-gas microscope. The same microscope setup enables us to detect the atoms in a two-dimensional optical lattice with single-lattice-site resolution.In the first part of this PhD project, we will use programmable light potentials to create a so-called Lieb lattice, by 'blocking' the central site in each 3x3 sub-cell of a square lattice with a repulsive potential (Fig. 2). Lieb lattices exhibit very interesting properties such as flat bands, localization and edge states. Based on model calculations which we have already done in collaboration with the local theory team in WP6, we would first use the site-resolved detection to confirm the existence of the of edge states, and study their dynamical evolution, and later do so as well in more complex lattice geometries. We will prepare initial states using another tailor-made light field that light-shifts selected atoms such that they can be transferred to a different hyperfine state with a microwave field, before all other atoms are removed. In a second project strand, we will use the tailor-made light-potentials to produce microscopic reservoirs with, e.g., varying chemical potential, atom numbers, and strength of the coupling link between them. We will focus on the observation thermodynamics properties in the quantum regime and investigate out-of-equilibrium dynamics and transport between the reservoirs, with the additional option to tune the onsite-interaction via a Feshbach resonance.