6 Soliton evolution at diffusive Kerr-type media is analyzed within the framework of the Helmholtz theory. The angular limitations of previous paraxial studies are overcome when both soliton propagation and diffusion of carriers are allowed to occur along any arbitrary direction. A model including two-dimensional carrier diffusion is proposed and its exact soliton solutions within the weakly nonlocal regime are presented. The restriction of carrier diffusion to a single transverse coordinate

more »

... ds to the breakdown of the rotational symmetry of the Helmholtz framework and soliton behavior becomes angular dependent. We study the impact of this limitation in an intrinsic angular scenario, such as a nonlinear interface.