Expérimental
Understanding the dynamics of entanglement and quantum information within a many-body system represents a central challenge in quantum physics, with far-reaching implications for the advancement of quantum technologies. The dynamic properties of the system depend strongly on the range of the interaction between the qubits. In this context, the coupling of cold atoms with the optical mode of a cavity offers a unique platform for engineering infinite long-range interactions between atoms, mediated by the cavity. At LKB, we have recently accomplished a significant milestone with the development of an experimental setup that combines a high-finesse optical microcavity, allowing us to work in the strong regime of cavity QED, with a high-numerical aperture lens. The combination of cavity-mediated long-range interactions between atoms and the local control offered by the tweezers opens up new avenues for engineering spatial correlations of entangled states and monitoring their propagation with single-particle resolution. In the realm of quantum simulations, this will allow us to investigate transport phenomena in spin systems. Furthermore, these spatially delocalized entangled states will serve as a resource to perform quantum-enhanced estimation of multiple parameters, a very promising new topic in the field of quantum metrology.