Ground state of alkaline-earth fermionic atoms in one-dimensional optical lattices

Abstract

We studied the ground state of alkaline-earth-metal atoms confined in one-dimensional optical lattices modeled by the Kondo lattice model plus a quadratic confining potential. We considered the half-filling case and both ferromagnetic and antiferromagnetic interaction between the localized and delocalized atoms. We found Kondo insulator domains that always coexist with metallic and/or band insulator regions. We observed that the on-site delocalized-localized spin correlation remains constant in the insulating regions and used it to determine the state diagrams. Metallic regions were found for both ferromagnetic and antiferromagnetic couplings.