Superfluid Fermi Gases with Large Scattering Length

We report quantum Monte Carlo calculations of superfluid Fermi gases with short-range two-body attractive interactions with infinite scattering length. The energy of such gases is estimated to be $(0.44\pm 0.01)$ times that of the noninteracting gas, and their pairing gap is approximately twice the energy per particle.

Figure 1

The optimum $\varphi (\mathbf{r})$ (solid lines) and the ${\varphi }_S$ (dashed lines) for $N=38$. Curves ending at $L/2$, $L/\sqrt{2}$, and $L\sqrt{3/4}$ are in the 001, 011, and 111 directions of the periodic box.

Figure 2

The momentum distribution of particles.

Figure 3

The $E(N)$ in units of $E_{\mathrm{F}\mathrm{G}}$.

Figure 4

The gap in units of $E_{\mathrm{F}\mathrm{G}}$.