Density-functional theory for fermions in the unitary regime

T. Papenbrock

doi:10.1103/physreva.72.041603

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arXiv · cond-mat/0507183

Density-functional theory for fermions in the unitary regime

T. Papenbrock

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Abstract

In the unitary regime, fermions interact strongly via two-body potentials that exhibit a zero range and a (negative) infinite scattering length. The energy density is proportional to the free Fermi gas with a proportionality constant $ξ$. We use a simple density functional parametrized by an effective mass and the universal constant $ξ$, and employ Kohn-Sham density-functional theory to obtain the parameters from fit to one exactly solvable two-body problem. This yields $ξ=0.42$ and a rather large effective mass. Our approach is checked by similar Kohn-Sham calculations for the exactly solvable Calogero model.

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T. Papenbrock. 2005-07-07. Density-functional theory for fermions in the unitary regime. https://doi.org/10.1103/physreva.72.041603

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