Fermionic atoms trapped in one-dimensional optical superlattice with harmonic confinement

Abstract

We study the ground-state properties of spin-1/2 fermionic atoms confined in a one-dimensional optical superlattice with harmonic confinement by using the density matrix renormalization group method. For this purpose, we consider an ionic Hubbard model that has superlattice potentials with 2-site periodicity. We find that several different types of insulating regimes coexist even if the number of atoms at each site is not an integer, but its average within the unit cell is an integer or half integer. This is contrasted to the coexisting phase of the metallic and Mott-insulating regimes known for the ordinary Hubbard model in an optical lattice. The phase characteristics are elucidated by investigating the profiles of the atom density, the local density/spin fluctuations, the double occupation probability and the spin correlations in detail.

8 pages, 9 figures, revised version, figures rearranged

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Cited by in corpus (6)

• Edge states and topological phases in one-dimensional optical superlattices
• Topological Mott insulators of ultracold atomic mixtures induced by interactions in one-dimensional optical superlattices
• Stripe Formation in Fermionic Atoms on 2-D Optical Lattice inside a Box Trap: DMRG Studies for Repulsive Hubbard Model with Open Boundary Condition
• Effects of disorder on atomic density waves and spin-singlet dimers in one-dimensional optical lattices
• Nonadiabatic Dynamics of Ultracold Fermions in Optical Superlattices
• Analysis of Particle Transfer by Periodic Lattice Modulation for Ultracold Fermionic Atom Systems in Three Dimensional Optical Lattice