Extended family of type II quadratic spatial solitons

Quadratic solitons consist of multifrequency beams which propagate together without diffraction, provided that the beams are strongly coupled via a second order nonlinearity. Such solitons can be excited with fundamental inputs only and occur during parametric down conversion. When the process is seeded with one or both orthogonally polarized inputs, a soliton is formed whose output is constant over a large range of input seed powers. The extended family of type II quadratic spatial solitons is discussed