  We consider a strongly repulsive two-component Fermi gas in a one-dimensional
(1D) optical lattice described in terms of a Hubbard Hamiltonian. We analyze
the response of the system to a periodic modulation of the hopping amplitude in
presence of large two body interaction. By (essentially) exact simulations of
the time evolution, we find a non-trivial double occupancy frequency
dependence. We show how the dependence relates to the spectral features of the
system given by the Bethe ansatz. The discrete nature of the spectrum is
clearly reflected in the double occupancy after long enough modulation time. We
also discuss the implications of the 1D results to experiments in higher
dimensional systems.
