Theory of the radiation trapping at the blue edge of supercontinuum and two-frequency quasi-solitons existing across the zero dispersion point

In this report, the remarkable effect of radiation trapping by solitons across zero dispersion point is discussed. The linear eigenfunction is numerically continued into the nonlinear regime and find associated bright-bright soliton pairs. An approximate analytical method to find soliton profiles is also developed. Leakage of the energy through the walls of the potential, dynamical effects in the regime when many modes of the trapped radiation are excited simultaneously and other soliton properties will be discussed. The starting model has been the generalized nonlinear Schrodinger (GNLS) equation widely used in the photonic crystal fiber (PCF) context. For finding the soliton profiles , reduction of the GNLS to the coupled NLS equations is used.