A new effective interaction for the trapped Fermi gas

Abstract

We apply the configuration-interaction method to calculate the spectra of two-component Fermi systems in a harmonic trap, studying the convergence of the method at the unitary interaction limit. We find that for a fixed regularization of the two-body interaction the convergence is exponential or better in the truncation parameter of the many-body space. However, the conventional regularization is found to have poor convergence in the regularization parameter, with an error that scales as a low negative power of this parameter. We propose a new regularization of the two-body interaction that produces exponential convergence for systems of three and four particles. From the systematics, we estimate the ground-state energy of the four-particle system to be (5.05 +- 0.024)hbar omega.

4 pages, 3 figures

References in corpus (7)

• Weakly bound dimers of fermionic atoms
• Local Density Functional Theory for Superfluid Fermionic Systems: The Unitary Gas
• Universal properties of a trapped two-component Fermi gas at unitarity
• Effective Theory for Trapped Few-Fermion Systems
• Unitary Fermi Gas in a Harmonic Trap
• BEC-BCS Crossover of a Trapped Two-Component Fermi Gas with Unequal Masses
• Single particle spectra based of modern effective interactions

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