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Journal of Physics Conference Series

Superfluidity of one-dimensional trapped fermionic optical lattices with spatially alternating interactions

Atsushi Yamamoto, Seiji Yunoki

Published Aug 12, 2013• 0 citations
Publisher

Abstract

Recent experiments have made it possible to spatially control local two-body interactions between ultracold atoms in inhomogeneous optical lattices. Motivated by this experimental progress, here we study theoretically one-dimensional trapped fermionic optical lattices with spatially modulated on-site interactions. The density matrix renormalization group method is used to examine the ground state phase diagram of a harmonically trapped Hubbard model with spatially alternating on-site repulsive interactions, U 1 and U 2 . With varying the strength of the harmonic trapping potential, we find a pair correlated metallic state in the ground state phase diagram, which can be stable only when U 1 ≠ U 2 . We discuss the properties of this possibly new state by examining various static physical quantities.

DOI
10.1088/1742-6596/454/1/012067

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