PME Special Quantum Seminar: Antoine Browaeys, Institut d'Optique

This talk will present effort to control and use the dipole interactions between cold atoms to implement spin Hamiltonians useful for quantum simulation of condensed matter or quantum optics situations. We rely on laser- cooled atomic ensembles. By exciting arrays of up to 100 atoms into Rydberg states, we make the atoms interact by the resonant dipole interaction. The system implements the XY spin 1⁄2 model, which exhibits various magnetic orders depending on the ferromagnetic or antiferromagnetic nature of the interaction. When the system is placed out of equilibrium, the interactions generate scalable spin squeezing. Analyzing the spread of correlations across the system, we measure the dispersion relation and observe the predicted anomalous behavior in the ferromagnetic case, a consequence of the dipolar interactions. Using an atomic ensemble driven on an optical transition, we also demonstrate the generation of non-classical light in a situation of superradiance.

Learn more