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## Direct control of high magnetic fields for cold atom experiments based on NV centers

In ultracold quantum gases, the interactions between the individual atoms can be controlled by applying magnetic bias fields. As magnetic field fluctuations limit the precision here, typically a feedback loop needs to be employed to regulate the …

## From the Jaynes–Cummings model to non-abelian gauge theories: a guided tour for the quantum engineer.

The design of quantum many body systems, which have to fulfill an extensive number of constraints, appears as a formidable challenge within the field of quantum simulation. Lattice gauge theories are a particular important class of quantum systems …

## A scalable realization of local U(1) gauge invariance in cold atomic mixtures

In the fundamental laws of physics, gauge fields mediate the interaction between charged particles. An example is quantum electrodynamics -- the theory of electrons interacting with the electromagnetic field -- based on $U(1)$ gauge symmetry. Solving …

## Quantized refrigerator for an atomic cloud

We propose to implement a quantized thermal machine based on a mixture of two atomic species. One atomic species implements the working medium and the other implements two (cold and hot) baths. We show that such a setup can be employed for the …

## Elastic Scattering Time of Matter Waves in Disordered Potentials

We report on the direct measurement of the elastic scattering time $\tau_S$ of ultracold atoms propagating in optical disordered potentials. By exploring this fundamental quantity over a large range of experimental parameters, we observe variations …

## Dynamical Topological Transitions in the Massive Schwinger Model with a $\theta$ Term

Aiming at a better understanding of anomalous and topological effects in gauge theories out-of-equilibrium, we study the real-time dynamics of a prototype model for CP-violation, the massive Schwinger model with a $\theta$-term. We identify dynamical …

## Ultracold atoms in disordered potentials: elastic scattering time in the strong scattering regime

We study the elastic scattering time $\tau_S$ of ultracold atoms propagating in optical disordered potentials in the strong scattering regime, going beyond the recent work of J. Richard et al., Phys. Rev. Lett. 122 100403 (2019). There, we identified …

## Coherent optical nano-tweezers for ultra-cold atoms

There has been a recent surge of interest and progress in creating subwavelength free-space optical potentials for ultracold atoms. A key open question is whether geometric potentials, which are repulsive and ubiquitous in the creation of …

## Quantum simulation of lattice gauge theories using Wilson fermions

Quantum simulators have the exciting prospect of giving access to real-time dynamics of lattice gauge theories, in particular in regimes that are difficult to compute on classical computers. Future progress towards scalable quantum simulation of …

## Implementing quantum electrodynamics with ultracold atomic systems

We discuss the experimental engineering of model systems for the description of QED in one spatial dimension via a mixture of bosonic $^23$Na and fermionic $^6$Li atoms. The local gauge symmetry is realized in an optical superlattice, using …