2017/08/14 by Faisal Etminan, Etminan, Faisal, Mohammad Mehdi Firoozabadi +1
Physics and Astronomy · #Advanced Chemical Physics Studies #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #Physics of Superconductivity and Magnetism #Rare-earth and actinide compounds #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.1708.04383
openalex publication_date 2017/08/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present calculations for spin 1/2 fermions at unitarity limit, where\nthe effective range of the interaction is zero and the scattering length is\ninfinite. We compute the ground-state energy for a system of 6, 10,14,18 and 20\nparticles, with equal numbers of up and down spins in a periodic cube in the\nfull ground-state constrained-path Monte Carlo (CPMC) method using the\nextended, attractive Hubbard model. Our results in a careful extrapolation to\nthe thermodynamic limit may suggest that the ratio of the ground-state energy\nto that of a free Fermi gas is \ξ = 0.43(4) , which can compare with recent\nexperimental results and consistent with the fixed node Green's function Monte\nCarlo and novel lattice approaches results. We also obtain results for\ninteractions with different effective ranges and find that the energy is\nconsistent with a universal linear dependence on the product of the Fermi\nmomentum and the effective range.\n