Abstract
We have continued the transposition of solid-state physics concepts to optical networks, this time focusing on the case of strong bonds corresponding to a luminous potential large in front of the recoil energy. In particular, we have introduced the concept of the Wannier function. In this strong bond limit, the tunneling of an atom from one site to another is only possible if the two sites are contiguous. Particle dynamics in the lattice can then be described by a highly simplified Hamiltonian, theHubbard Hamiltonian, whose main properties we have described. We have also discussed the role played by interactions in a lattice, focusing on the stabilization of dimers occupying the same site.
