Probing correlations of gaseous microwires in lattice potentials via inelastic light scattering

In this work, inelastic light-scattering (Bragg spectroscopy) is used to study strongly correlated phases of ultracold 1D gases in optical lattices. We investigate the crossover from correlated superfluids to Mott insulators. Light-scattering creates in the system elementary excitations with non-zero momentum, and the response of the correlated gases is in the linear regime. This allows for extracting information about the atomic many-body state in terms of its particle-hole excitations, as common in solid-state physics. In particular, we characterize the Mott state both via intra-band and inter-band spectroscopy, the former giving access to the dynamical structure factor S(q, ω) and the latter to the one-particle spectral function A(q, ω).