Stationary trapping of light beams in bulk second-order nonlinear media

The mutual trapping of fundamental and second harmonic, continuous-wave light beams propagating in bulk second-order nonlinear media is studied. We find numerically families of stationary, radially symmetric solitary waves. The transverse profiles of the trapped beams, their scaling properties, and their stability under propagation are investigated as a function of the total power and the linear wavevector-mismatch between the waves. We show that at phase-matching mutually trapped solitary waves exist for any total wave power, whereas they exist only above a threshold power for both positive and negative phase-mismatches.