Numerically exact simulations of strongly interacting fermions in an optical lattice

Marcos Rigol, Alejandro Muramatsu

J. P. Kestner, Luming Duan

Ehsan Khatami, Marcos Rigol

We study finite-temperature properties of strongly correlated fermions in two-dimensional optical lattices by means of numerical linked cluster expansions, a computational technique that allows one to obtain exact results in the thermodynamic limit. We focus our analysis on the strongly interacting regime, where the on-site repulsion is of the order of or greater than the band width. We compute the equation of state, double occupancy, entropy, uniform susceptibility, and spin correlations for temperatures that are similar to or below the ones achieved in current optical lattice experiments. We provide a quantitative analysis of adiabatic cooling of trapped fermions in two dimensions, by means of both flattening the trapping potential and increasing the interaction strength.

Zhihao Xu, Shu Chen

We demonstrate that the static structure factor, momentum distribution, and density distribution provide clear signatures of the emergence of Wigner crystal for the fermionic dipolar gas with strongly repulsive dipole-dipole interactions trapped in one-dimensional optical lattices. Our numerical evidences are based on the exact diagonalization of the microscopic effective lattice Hamiltonian of few particles interacting with long-range interactions. As a comparison, we also study the system with only nearest-neighbor interactions, which displays quite different behavior from the dipolar system in the regime of strong repulsion.

Ariel Sommer, Lawrence W. Cheuk, Mark Ku +3 more

Tilman Esslinger