DYNAMICAL EFFECTS OF THE DIPOLE-DIPOLE INTERACTION IN 3-DIMENSIONAL OPTICAL LATTICES

We present a many-body theory of the dipole-dipole interaction in thre e-dimensional optical lattices generated by a four-beam configuration, specializing to the case of J(g) = 1/2 --> J(e) = 3/2 transitions. We construct a many-body interaction Hamiltonian in coordinate represent ation for an antiferromagnetic fee optical lattice, the Schrodinger fi eld operators being expanded on a basis of Wannier functions. We discu ss the main characteristics of the dipole-dipole matrix elements givin g rise to bound-bound and bound-free atom interactions in the lattice. Because of the anisotropy of the dipole-dipole interaction, specific directions can be favored for transport and scattering processes. Furt hermore, since the dipole-dipole interaction depends on atomic magneti c quantum numbers, the dipole-dipole potential resembles a spin-depend ent potential, and can give rise to atomic hopping with simultaneous c hange in the magnetic quantum number. [S1050-2947(98)00502-2].