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arXiv · 0804.2223

Mott-Insulator Transition for Ultracold Fermions in Two-Dimensional Optical Lattices

N. Goldman
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Abstract

In this work we study ultracold Fermions confined in a two-dimensional optical lattice and we explore the Mott-insulator transition with the Fermi-Hubbard model. On the basis of a mean-field approach, we study the phase diagrams in the presence of a harmonic trapping potential. Local Mott-insulator phases are shown to be generally situated in the center of the trap and correspond to a vanishing variance of the local density. We then study the effects induced by rotation on the Mott-insulator phase transition. In particular, we show that the phase boundary reproduces the edge of the Hofstadter butterfly.

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N. Goldman. 2008-04-18. Mott-Insulator Transition for Ultracold Fermions in Two-Dimensional Optical Lattices. https://doi.org/10.1103/physreva.77.053406

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