Atom-resolved Microscopy of 2D Bose and Fermi Gases in the Continuum

Quantum gas microscopy is a powerful technique that has been widely employed in experiments on lattice-trapped gases. However, the study of quantum gases in the continuum has been limited to more coarse-grained probes such as absorption imaging. Here we report atom-resolved detection of itinerant bosonic ²³Na and fermionic ⁶Li quantum gases in the continuum, which enables the direct in situ measurement of interparticle correlations. We observe Bose-Einstein condensation with single-atom resolution, measure the enhancement of two-particle g⁽²⁾ correlations of thermal bosons, and detect the suppression of g⁽²⁾ for fermions, corresponding to the Fermi or exchange hole. For strongly interacting two-dimensional Fermi gases, we directly observe non-local fermionic pairs in the BEC-BCS crossover. We employ spin-resolved imaging to directly characterize spinful pair correlations, from which we can obtain the pairing gap, the pair size, and the short-range contact. In situ thermometry is enabled via the fluctuation-dissipation theorem. Our technique opens the door to the atom-resolved study of strongly correlated quantum gases of bosons, fermions, and their mixtures.