Characterizing phases of the two dimensional repulsive Fermi Hubbard model using local correlators

Cold atom systems provide a rich platform to realize strongly interacting condensed matter systems, and recent progress in fluorescence imaging technique [1,2] has enabled identification of non-trivial doublon, singlon and holon correlation functions. We report a DQMC study of such correlation functions in the two dimensional repulsive Fermi Hubbard model as a function of density, in corroboration with recent experimental findings [2]. We identify density-dependent suppression of holon-holon and doublon-doublon correlations. On the other hand, the singlon correlations with other singlon, or with holons and doublons, show non-trivial density dependent structure. We provide a parton construction which allows us to get insights into the nature of these different correlations.