Nonlinear interaction effect on the phase distribution in one-dimensional disordered lattices

We studied in this paper the effect of nonlinear interaction on the PD of a one-dimensional Kronig-Penney chain. In the quasi-ballistic regime (L « (2k_F)^-1 « λ (localization length)), an attractive nonlinear potential leads to a smooth peak with an oscillatory shift in its position, while for repulsive potentials the peak becomes sharper and moves towards π. In the quasi-metallic regime ((2k_F)^-1 « L « λ), the uniform PD becomes peaked as we increase the nonlinear potential. Depending on the sign of the nonlinear potential, this peak moves either away from or closer to π. In the strong disorder regime, the nonlinearity plays an identical role to disorder. It was found that the overall effect of nonlinear interaction in the mixed disorder case can be interpreted as a superposition of those for potential barriers and wells treated separately. Further results and discussion are also provided.