Metal And Insulator States Of Su(6) X Su(2) Clusters Of Fermions In One-Dimensional Optical Lattices

We studied the behavior of mixtures of Yb-173 (with symmetry up to SU(6)) and Yb-171 (up to SU(2)) fermionic isotopes loaded in one-dimensional (1D) optical lattices. To do so, we solved the Schrodinger equation describing different systems using a diffusion Monte Carlo technique. We considered continuous Hamiltonians in which the interactions between atoms of different species (isotopes and/or spins) were modeled by contact potentials with parameters derived from their experimental scattering lengths. This implies that we can find both attractive and repulsive interactions between fermion pairs in the same cluster. The strength of those interactions can be changed by varying the transverse confinement, leading to different cluster behaviors. Only balanced clusters, i.e. with the same number of Yb-173 and Yb-171 atoms were considered. We found that the standard state for these clusters is a metallic-like one with different populations of Yb-173-Yb-171 molecule-like pairs in each optical lattice potential well. However, for big enough clusters, insulator-like states are also possible.