Felix Palm

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The study of interacting quantum Hall states and their exotic anyonic excitations poses a major challenge in current experimental and theoretical research. Quantum simulators, in particular cold atoms in optical lattices, provide a promising platform to realize, manipulate, and understand such systems with unprecedented control. In this talk, I will discuss how the local spin and density resolution of quantum gas microscopes extends the toolbox of quantum Hall physics with an emphasis on spinful, fermionic systems.

First, I will discuss the interplay of spin and charge in quantum Hall states, resulting in ferromagnetism and skyrmionic spin-textures [1,2]. I will show how different types of interactions lead to the stability of different classes of states and will present experimentally relevant signatures to identify these states.

Then, I will turn towards a fundamental question regarding the topological order of quantum Hall states: the speculated condensation of composite bosons exhibiting quasi long-range order. I will exemplify this mechanism in fermionic [2] and bosonic [3] systems and touch upon its detectability in tensor network simulations and quantum gas microscopes.

[1] Palm et al., Ferromagnetism and skyrmions in the Hofstadter–Fermi–Hubbard model; NJP 25 (2023)

[2] Pauw et al., From hidden order to skyrmions: Quantum Hall states in an extended Hofstadter-Fermi-Hubbard model; arXiv:2509.12184 (2025)

[3] Pauw et al., Detecting Hidden Order in Fractional Chern Insulators; PRR 6 (2024)

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Université Libre de Bruxelles
0.03
Contact: Matteo Rizzi