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arXiv · 0804.3280

Interband physics in an ultra-cold Fermi gas in an optical lattice

J. -P. Martikainen·E. Lundh·T. Paananen
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Abstract

We study a gas of strongly polarized cold fermions in an optical lattice when the excited p-bands are populated. We derive the relevant Hamiltonian and discuss the expected phase diagram for both repulsive and attractive interactions. In the parameter regime covered here, checkerboard anti-ferromagnetic ordering is found to be possible for repulsive interactions while for attractive interactions, transitions between different types of paired phases are predicted.

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J. -P. Martikainen, E. Lundh, T. Paananen. 2008-04-21. Interband physics in an ultra-cold Fermi gas in an optical lattice. https://doi.org/10.1103/physreva.78.023607

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