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Ground state energy of spin-1/2 fermions in the unitary limit

Dean Lee
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Abstract

We present lattice results for the ground state energy of a spin-1/2 fermion system in the unitary limit, where the effective range of the interaction is zero and the scattering length is infinite. We compute the ground state energy for a system of 6, 10, 14, 18, and 22 particles, with equal numbers of up and down spins in a periodic cube. We estimate that in the limit of large number of particles, the ground state energy is 0.25(3) times the ground state energy of the free Fermi system.

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Dean Lee. 2006-01-06. Ground state energy of spin-1/2 fermions in the unitary limit. https://doi.org/10.1103/physrevb.73.115112

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