Antiferromagnetic Correlations in Two-Dimensional Fermionic Mott-Insulating and Metallic Phases.

@article{Drewes2017AntiferromagneticCI,
  title={Antiferromagnetic Correlations in Two-Dimensional Fermionic Mott-Insulating and Metallic Phases.},
  author={J. H. Drewes and L. A. Miller and Eugenio Cocchi and C. F. Chan and N. Wurz and M. Gall and Daniel Pertot and Ferdinand Brennecke and Michael K{\"o}hl},
  journal={Physical review letters},
  year={2017},
  volume={118 17},
  pages={
          170401
        }
}
We experimentally study the emergence of antiferromagnetic correlations between ultracold fermionic atoms in a two-dimensional optical lattice with decreasing temperature. We determine the uniform magnetic susceptibility of the two-dimensional Hubbard model from simultaneous measurements of the in situ density distribution of both spin components. At half filling and strong interactions our data approach the Heisenberg model of localized spins with antiferromagnetic correlations. Moreover, we… 

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