Comment on “Novel Superfluidity in a Trapped Gas of Fermi Atoms with Repulsive Interaction Loaded on an Optical Lattice”

A Comment on the Letter by M. Machida et al., Phys. Rev. Lett. 93, 200402 (2004). The authors of the Letter offer a Reply.

Figure 1

QMC (points) and DMRG (continuous lines) results for $E_b(10)=E(5,5)+E(6,6)-2E(5,6)$ vs $U/t$ for: $V=7.5t$ (red ▽, green ○) and $V=9.5t$ (cyan ◇, blue △) (see I), when the center of the trap is located in the middle of two lattice points (red ▽, cyan ◇) and in a lattice point (green ○, blue △). The dashed line shows ED results for $E_b(10)$ in open MI systems (see text). The inset shows ED results for $E_G^{*}=E_G+A{N}_f$ vs $N_f$, in open MI systems with $U/t=8$. Here we choose a nonzero value of $A=0.327$ to stress the even(green ×)-odd(red +) effect, without affecting the actual value of $E_b<0$ it causes.