The stability and free expansion of a dipolar Fermi gas

We investigate the stability and the free expansion of a trapped dipolar Fermi gas. We show that stabilizing the system relying on tuning the trap geometry is generally inefficient. We further show that the expanded density profile always gets stretched along the attractive direction of dipolar interaction. We also point out that by switching off the dipolar interaction simultaneously with the trapping potential, the deformation of momentum distribution can be directly observed.