We show that resonant wave mixing that is due to quadratic nonlinearity can support stable bright spatial solitons, even in the most counterintuitive case of a bulk medium with defocusing Kerr nonlinearity. We analyze the structure and stability of such self-guided beams and demonstrate that they can be generated from a Gaussian input beam, provided that its power is above a certain threshold.
© 1997 Optical Society of America
Ole Bang, Yuri S. Kivshar, and Alexander V. Buryak, "Bright spatial solitons in defocusing Kerr media supported by cascaded nonlinearities," Opt. Lett. 22, 1680-1682 (1997)