  We report on the experimental realization of a photonic system that simulates
the one-dimensional two-particle Hubbard model. This analogy is realized by
means of two-dimensional arrays of coupled optical waveguides, fabricated using
femtosecond laser inscription. By tuning the analogous "interaction strength",
we reach the strongly-interacting regime of the Hubbard Hamiltonian, and
demonstrate the suppression of standard tunneling for individual "particles".
In this regime, the formation of bound states is identified through the direct
observation of pair tunneling. We then demonstrate the coherent destruction of
tunneling (CDT) for the paired particles in the presence of an engineered
oscillating force of high frequency. The precise control over the analogous
"interaction strength" and driving force offered by our experimental system
opens an exciting route towards quantum simulation of few-body physics in
photonics.
