Scattering of dipole-mode vector solitons: theory and experiment.

We study, both theoretically and experimentally, the scattering properties of optical dipole-mode vector solitons-radially asymmetric composite self-trapped optical beams. First, we analyze the soliton collisions in an isotropic two-component model with a saturable nonlinearity, and demonstrate that in many cases the scattering dynamics of the dipole-mode solitons allows us to classify them as "molecules of light"-extremely robust spatially localized objects which survive a wide range of interactions and display many properties of composite states with a rotational degree of freedom. Next, we study the composite solitons in an anisotropic nonlinear model that describes photorefractive nonlinearities, and also present a number of experimental verifications of our analysis.