  We study the dynamics and thermalization of strongly correlated fermions in
finite one-dimensional lattices after a quantum quench. Our calculations are
performed using exact diagonalization. We focus on one- and two-body
observables such as the momentum distribution function [n(k)] and the
density-density structure factor [N(k)], respectively, and study the effects of
approaching an integrable point. We show that while the relaxation dynamics and
thermalization of N(k) for fermions is very similar to the one of hardcore
bosons, the behavior of n(k) is distinctively different. The latter observable
exhibits a slower relaxation dynamics in fermionic systems. We identify the
origin of this behavior, which is related to the off-diagonal matrix elements
of n(k) in the basis of the eigenstates of the Hamiltonian. More generally, we
find that thermalization occurs far away from integrability and that it breaks
down as one approaches the integrable point.
