2003/07/31 by H. Heiselberg, Henning Heiselberg
Chemistry · Physics and Astronomy · #Advanced Physical and Chemical Molecular Interactions #Cold Atom Physics and Bose-Einstein Condensates #Physics of Superconductivity and Magnetism #cond-mat.supr-con
paper · pdf · doi:10.1088/0953-4075/37/7/060
published as J.Phys.B: At.Mol.Opt.PHys. 37 (2004) 1-13 · Revised version extended to include recent molecular BEC-BCS results
arxiv created 2004/02/06 · openalex publication_date 2004/03/24 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
Near Feshbach resonances, n | a | 3 ≫ 1, systems of Bose and Fermi particles become strongly interacting/dense. In this unitary limit both bosons and fermions have very different properties than in a dilute gas, e.g., the energy per particle approaches a value ℏ 2 n 2/3 / m times a universal many-body constant. Calculations based upon an approximate Jastrow wavefunction can quantitatively describe recent measurements of trapped Bose and Fermi atoms near Feshbach resonances. The pairing gap between attractive fermions also scales as Δ ∼ ℏ 2 n 2/3 / m near Feshbach resonances and is a large fraction of the Fermi energy—promising for observing BCS superfluidity in traps. Pairing undergoes several transitions depending on interaction strength and the number of particles in the trap and can also be compared with pairing in nuclei.