Exploring strongly correlated Bose gases by light scattering: the superfluid to Mott insulator cross-over

In condensed-matter physics, inelastic light-scattering provides a powerful method to investigate the system under study. It allows accessing the correlation functions which could identify dierent many-body states. We will report on the investigation of ultracold atoms in optical potentials, which have proved to be an excellent way of realizing simplied models of condensed-matter physics theory in experimental practice. In particular, we studied the modication of the response of an array of one-dimensional samples of 87Rb in a periodic potential across the superfluid to Mott-insulator transition, extracting information about both the dynamical spectral function and the one-particle spectral function.