Quantum simulation has the potential to investigate gauge theories in strongly-interacting regimes, which are up to now inaccessible through conventional numerical techniques. Here, we take a first step in this direction by implementing a Floquet-based method for studying Z 2 lattice gauge theories using two-component ultracold atoms in a double-well potential. For resonant periodic driving at the on-site interaction strength and an appropriate choice of the modulation parameters, the effective Floquet Hamiltonian exhibits Z 2 symmetry. We study the dynamics of the system for different initial states and critically contrast the observed evolution with a theoretical analysis of the full time-dependent Hamiltonian of the periodically-driven lattice model. We reveal challenges that arise due to symmetrybreaking terms and outline potential pathways to overcome these limitations. Our results provide important insights for future studies of lattice gauge theories based on Floquet techniques.Lattice gauge theories (LGTs) [1,2] are fundamental for our understanding of quantum many-body physics across different disciplines ranging from condensed matter [3-6] to high-energy physics [7]. However, theoretical studies of LGTs can be extremely challenging in particular in strongly-interacting regimes, where conventional computational methods are limited [8,9]. To overcome these limitations alternative numerical tools are currently developed, which enable out-of-equilibrium and finite density computations [10][11][12][13]. In parallel, the rapid progress in the field of quantum simulation [14][15][16][17] has sparked a growing interest in designing experimental platforms to explore the rich physics of LGTs [18][19][20][21][22][23][24][25]. State-of-the-art experiments are now able to explore the physics of static [26] as well as density-dependent gauge fields [27] and have engineered controlled few-body interactions [28][29][30], which are the basis for many proposed schemes to realize LGTs. First studies of the Schwinger model have been performed with quantum-classical algorithms [31] and a digital quantum computer composed of four trapped ions [32]. The challenge for analog quantum simulators mainly lies in the complexity to engineer gauge-invariant interactions between matter and gauge fields.Here, we explore the dynamics of a minimal model for Z 2 LGTs coupled to matter with ultracold atoms in periodically-driven double-well potentials [33]. An alternative technique was recently proposed for digital quantum simulation [34]. Z 2 LGTs are of high interest in condensed matter physics [13,[35][36][37] and topological quantum computation [38]. Our scheme is based on densitydependent laser-assisted tunneling techniques [39][40][41][42]. We use a mixture of bosonic atoms in two different internal states to encode the matter and gauge field degrees of freedom. The interaction between these states is engineered via resonant periodic modulation [43][44][45][46] of the on-site potential at the inter-species Hubbard interaction [47][48...

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We investigate inelastic collision dynamics of a single cold ion in a Bose-Einstein condensate. We observe rapid ion-atom-atom three-body recombination leading to formation of weakly bound molecular ions followed by secondary two-body molecule-atom collisions quenching the rovibrational states towards deeper binding energies. In contrast to previous studies exploiting hybrid ion traps, we work in an effectively field-free environment and generate a free low-energy ionic impurity directly from the atomic ensemble via Rydberg excitation and ionization. This allows us to implement an energy-resolved field-dissociation technique to trace the relaxation dynamics of the recombination products. Our observations are in good agreement with numerical simulations based on Langevin capture dynamics and provide complementary means to study stability and reaction dynamics of ionic impurities in ultracold quantum gases.