Fermionic Fractional Quantum Hall Systems under the Microscope

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Fractional quantum Hall (FQH) states are paradigmatic examples of strongly correlated topological quantum matter, combining geometric order and strong interparticle interactions. Yet, limited microscopic control in solid-state platforms often restricts observations to global current or spectroscopy probes. Engineered quantum systems, such as ultracold atoms in optical lattices, offer a complementary route for exploring topological order leveraging precise control over Hamiltonian parameters and access to local observables through quantum gas microscopy. The primary goal of this project is to prepare and probe quantum-engineered fermionic FQH states for the first time in a next-generation quantum gas microscope. First, we will implement direct laser cooling of fermionic Li-6 atoms to efficiently prepare individual atoms in the ground state of optical tweezers, and holographically project lattice potentials to assemble Fermi-Hubbard systems atom by atom. To explore FQH physics, we will implement small fermionic Harper-Hofstadter systems via Floquet engineering. Leveraging our system’s excellent coherence, we will extend observations beyond two particles and perform first observations fractionally charged quasi-hole excitations pinned by local repulsive potentials. To access a broader class of fermionic FQH states, we will build upon recent advances in multi-orbital lattices and engineer p-wave interactions between pairs of spinless fermions. This approach will facilitate first microscopic studies of exotic Pfaffian states. Our results will significantly impact research in quantum simulation and topological physics. Technically, we will advance programmable optical lattices, enabling sub-second cycle times and unprecedented levels of control in quantum gas microscopes. Implementing p-wave interactions will facilitate the exploration of Pfaffian states and non-Abelian excitations, which are building blocks for fault-tolerant topological quantum computing.