We demonstrate that a weak defocusing Kerr effect in an optical medium with predominantly quadratic [or χ(2)] nonlinear response can eliminate the parametric modulational instability of plane waves, leading to the existence of stable two-wave dark and vortex spatial solitons.
© 1998 Optical Society of America
Tristram J. Alexander, Alexander V. Buryak, and Yuri S. Kivshar, "Stabilization of dark and vortex parametric spatial solitons," Opt. Lett. 23, 670-672 (1998)