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arXiv · 1012.5474

Momentum Distribution and Contact of the Unitary Fermi gas

Joaquín E. Drut·Timo A. Lähde·Timour Ten
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Abstract

We calculate the momentum distribution n(k) of the Unitary Fermi Gas using Quantum Monte Carlo calculations at finite temperature T/\epsilon_F as well as in the ground state. At large momenta k/k_F, we find that n(k) falls off as C/k^4, in agreement with the Tan relations. From the asymptotics of n(k), we determine the contact C as a function of T/\epsilon_F and present a comparison with theory. At low T/\epsilon_F, we find that C increases with temperature, and we tentatively identify a maximum around T/\epsilon_F \simeq 0.4. Our calculations are performed on lattices of spatial extent up to N_x = 14 with a particle number per unit volume of \simeq 0.03 - 0.07.

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Joaquín E. Drut, Timo A. Lähde, Timour Ten. 2010-12-25. Momentum Distribution and Contact of the Unitary Fermi gas. https://doi.org/10.1103/physrevlett.106.205302

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