Probing Fermi-Hubbard systems in and out of equilibrium

Date: May 24, 2019
Time: 11:50 AM - 12:15 PM (Local Time Germany)
Speaker: Dr. Guillaume Salomon
Location: 17 Oxford St, Cambridge, MA
Room: Jefferson 250

This talk was held by Dr. Guillaume Salomon at the MPHQ Spring Scientific Meeting in Harvard. The Fermi-Hubbard model, describing interacting fermions on a lattice, offers a simple framework to study strongly correlated fermionic phases. Closely related to the physics of high-temperature superconductors, the interplay between doping and magnetism in this model manifests itself very differently in one and two dimensions.

The Fermi-Hubbard model, describing interacting fermions on a lattice, offers a simple framework to study strongly correlated fermionic phases. Closely related to the physics of high-temperature superconductors, the interplay between doping and magnetism in this model manifests itself very differently in one and two dimensions.
We discuss here first the out of equilibrium dynamics of spin and density degrees of freedom following a quench in one dimension. Using spin-resolved quantum gas microscopy we directly observe the spin-charge deconfinement dynamics after the removal of one fermion from the Hubbard chain.
We then contrast these results with the measurement of equilibrium correlations in particle-doped twodimensional Hubbard systems. We detect here a local reduction of the spin correlations in the direct vicinity of the double occupancies. We interpret it as the dressing cloud of a magnetic polaron and demonstrate that it originates from the competition between kinetic and magnetic energy.