Fermionic quantum carpets: From canals and ridges to solitonlike structures

We report a formation of sharp, solitonlike structures in an experimentally accessible ultracold Fermi gas, as a quantum carpet solution is analyzed in a many body system. The effect is perfectly coherent in a noninteracting gas, but in the presence of repulsive interaction in a two-component system, the structures vanish at a finite time. As they disappear, the system enters a dynamical equilibrium, in which kinetic energies of atoms tend to the same average value. The coherence is revived in a strong interaction regime, with the onset of phase separation, and with a double quantum carpet appearing.