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

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.

7 pages, 7 figures, to appear in Physical Review A

References in corpus (10)

• Local quantum criticality in confined fermions on optical lattices
• Interaction-controlled transport of an ultracold Fermi gas
• Mott transition of fermionic atoms in a three-dimensional optical trap
• Effective magnetic fields in degenerate atomic gases induced by light beams with orbital angular momenta
• Vortex configurations of bosons in an optical lattice
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• Vortex lattices of bosons in deep rotating optical lattices
• Characterization of topological states on a lattice with Chern number
• Spatial patterns in optical lattices submitted to gauge potentials