Quantum Antiferromagnetism of Fermions in Optical Lattices with Half-filled p-band

Abstract

We study Fermi gases in a three-dimensional optical lattice with five fermions per site, i.e. the s-band is completely filled and the p-band with three-fold degeneracy is half filled. We show that, for repulsive interaction between fermions, the system will exhibit spin-3/2 antiferromagnetic order at low temperature. This conclusion is obtained in strong interaction regime by strong coupling expansion which yields an isotropic spin-3/2 Heisenberg model, and also in weak interaction regime by Hatree-Fock mean-field theory and analysis of Fermi surface nesting. We show that the critical temperature for this antiferromagnetism of a p-band Mott insulator is about two orders of magnitudes higher than that of an $s$-band Mott insulator, which is close to the lowest temperature attainable nowadays.

References in corpus (3)

• Flat bands and Wigner crystallization in the honeycomb optical lattice
• State preparation and dynamics of ultracold atoms in higher lattice orbitals
• Prediction of quantum stripe ordering in optical lattices

Cited by in corpus (8)

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• Experimental realization of a high precision tunable hexagonal optical lattice
• Interband physics in an ultra-cold Fermi gas in an optical lattice
• Density-Wave and Antiferromagnetic States of Fermionic Atoms in Optical Lattices
• Multiband effects on the conductivity for a multiband Hubbard model