Large phase difference of soliton-like mutually-trapped beam pairs in strong nonlocal media

We discuss the propagation of two orthogonally polarized beams in nonlocal planar waveguides by variational approach as well as a numerical method. The evolution equations for parameters and the critical powers for soliton-like mutually-trapped propagation of the two beams are obtained. Moreover, we analyze the influence of coupling coefficient, initial power, birefringence and the degree of nonlocal on mutually-trapped propagation. In addition, we find that the two beams will have large phase difference since phase shifts of the two beams are different under certain conditions. This theoretical result may have potential applications in the light-control-light technology.