Pairing in two-dimensional Fermi gases with a coordinate-space potential

Abstract

In this work we theoretically study pairing in two-dimensional Fermi gases, a system which is experimentally accessible using cold atoms. We start by deriving the mean-field pairing gap equation for a coordinate-space potential with a finite interaction range, and proceed to solve this numerically. We find that for sufficiently short effective ranges the answer is identical to the zero-range one. We then use Diffusion Monte Carlo to evaluate the total energy for many distinct particle numbers; we employ several variational parameters to produce a good ground-state energy and then use these results to extract the pairing gap across a number of interaction strengths in the strongly interacting two-dimensional crossover. Extracting the gap via the odd-even energy staggering, our microscopic results can be used as benchmarks for other theoretical approaches.

9 pages, 10 figures; v2 corresponds to published version

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Cited by in corpus (5)

• The ${}^1$S${}_0$ pairing gap in neutron matter
• Quantum Monte Carlo simulations of two-dimensional repulsive Fermi gases with population imbalance
• Brueckner $G$-matrix approach to two-dimensional Fermi gases with the finite-range attractive interaction
• Precision thermodynamics of the strongly interacting Fermi gas in two dimensions
• Finite-range effect in the two-dimensional density-induced BCS-BEC crossover