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arXiv · 0904.4610

Mott transitions in ternary flavor mixtures of ultracold fermions on optical lattices

Abstract

Ternary flavor mixtures of ultracold fermionic atoms in an optical lattice are studied in the case of equal, repulsive on-site interactions U>0. The corresponding SU(3) invariant Hubbard model is solved numerically exactly within dynamical mean-field theory using multigrid Hirsch-Fye quantum Monte Carlo simulations. We establish Mott transitions close to integer filling at low temperatures and show that the associated signatures in the compressibility and pair occupancy persist to high temperatures, i.e., should be accessible to experiments. In addition, we present spectral functions and discuss the properties of a ``semi-compressible'' state observed for large U near half filling.

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BibTeXRIS

E. V. Gorelik, N. Blümer. 2009-04-29. Mott transitions in ternary flavor mixtures of ultracold fermions on optical lattices. https://doi.org/10.1103/physreva.80.051602

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