  Dynamical properties of a few ultra-cold fermions confined in a double-well
potential is studied. We show that the dynamics, which is governed by
single-particle tunnelings for vanishing interactions, is completely different
for strong interactions. Depending on the details of the configuration, for
sufficiently strong interactions (repulsions or attractions) the particle flow
through the barrier can be accelerated or slowed down. This effect cannot be
explained with the single-particle picture. It is clarified with direct
inspection to the spectrum of the few-body Hamiltonian.
