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arXiv · 1405.0543

Effective orbital ordering in multiwell optical lattices with fermionic atoms

A. M. Belemuk·N. M. Chtchelkatchev·A. V. Mikheyenkov
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Abstract

We consider the behavior of Fermi atoms on optical superlattices with two-well structure of each node. Fermions on such lattices serve as an analog simulator of Fermi type Hamiltonian. We derive a mapping between fermion quantum ordering in the optical superlattices and the spin-orbital physics developed for degenerate $d$-electron compounds. The appropriate effective spin-orbital model appears to be the modification of the Kugel-Khomskii Hamiltonian. We show how different ground states of this Hamiltonian correspond to particular spin-pseudospin arrangement patterns of fermions on the lattice. The dependence of fermion arrangement on phases of complex hopping amplitudes is illustrated.

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A. M. Belemuk, N. M. Chtchelkatchev, A. V. Mikheyenkov. 2014-05-03. Effective orbital ordering in multiwell optical lattices with fermionic atoms. https://doi.org/10.1103/physreva.90.023625

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