Martin Zwierlein


Strongly Interacting Fermi Gases under the Microscope



Strongly interacting fermions govern the physics of e.g. high-temperature superconductors, nuclear matter and      
neutron stars. The interplay of the Pauli principle with strong interactions can give rise to exotic properties    
that we do not even understand at a qualitative level. In recent years, ultracold Fermi gases of atoms have        
emerged as a pristine platform for the creation and study of strongly interacting systems of fermions. Near        
Feshbach resonances, such gases display superfluidity at 17% of the Fermi temperature. Scaled to the density of    
electrons in solids, this corresponds to superfluidity far above room temperature. Confined in optical lattices,   
fermionic atoms realize the Fermi-Hubbard model, believed to capture the essence of cuprate high-temperature
superconductors. In recent experiments on two-dimensional Fermi gases under a microscope, we observe metallic,
Mott insulating and band insulating states with single-site, single-atom resolution. The microscope allows for     
the site-resolved detection of charge and spin correlations, revealing the famous Pauli and correlation hole for   
low and intermediate lattice fillings, and correlated doublon-hole pairs near half filling. These correlations     
should play an important role for transport in the Fermi-Hubbard model. 



Coffee and Tea at 4:30 p.m.