Expérimental
Our team has built a new ultracold strontium experiment to study the relaxation dynamics of quantum gases in two-dimensional optical lattices using single-atom resolved fluorescence microscopy. Recent theoretical advances have put forward a very simple picture: the dynamics of such system would be essentially local, meaning that it would take a finite time for correlations between two distant regions of space to reach their equilibrium value, as happens in relativistic theory because of the limit imposed by the speed of light. This locality would be an emergent collective property, similar to spontaneous symmetry breaking, and have its origin in the propagation of quasiparticle excitations. The intern will join a team of two PhD students, learn how to run the experiment, and directly participate in the first measurements of the propagation of correlations. The idea is to study of the relaxation dynamics of the after a so-called quantum quench. In practice, the gas will initially be prepared in the ground state of the optical lattice and then set out of equilibrium by suddenly varying the lattice depth. Of particular interest will be the quantum critical region in the vicinity of the superfluid-to-Mott insulator transition, where quasiparticles are expected to be strongly interacting, and therefore cannot be the carrier of ballistically propagating correlations, which goes against the simple picture described above. The intern is expected to pursue with a PhD thesis.