Density-Wave and Antiferromagnetic States of Fermionic Atoms in Optical Lattices

Abstract

We study the two-band effects on ultracold fermionic atoms in optical lattices by means of dynamical mean-field theory. We find that at half-filling the atomic-density-wave (ADW) state emerges owing to the two-band effects in the attractive interaction region, while the antiferromagnetic state appears in the repulsive interaction region. As the orbital splitting is increased, the quantum phase transitions from the ADW state to the superfluid state and from the antiferromagnetic state to the metallic state occur in respective regions. Systematically changing the orbital splitting and the interaction, we obtain the phase diagram at half-filling. The results are discussed using the effective boson model derived for the strong attractive interaction.

7 pages, 7 figures

References in corpus (5)

• Antiferromagnetic Order of Strongly Interacting Fermions in a Trap: Real-Space Dynamical Mean-Field Analysis
• Mott transition of fermionic atoms in a three-dimensional optical trap
• Supersolid state of ultracold fermions in an optical lattice
• Magnetic and superfluid phases of confined fermions in two-dimensional optical lattices
• Mott-Insulator Transition for Ultracold Fermions in Two-Dimensional Optical Lattices