Resonance induced by a bound state in the continuum in a two-level nonlinear Fano-Anderson model

We consider the transmission through a nonlinear media in the framework of a two-level nonlinear Fano-Anderson model. The model is realized in photonic crystal waveguide coupled with two off-channel defects with the instantaneous Kerr-type nonlinearity. We reveal a resonance and argue that it is a result of excitement of bound state in the continuum (BSC) by transmitted wave. The resonance induced by BSC is located at the energy of BSC with a width proportional to the amplitude of incident wave. The BSC exists at any distance between energy levels of the two-level nonlinear Fano-Anderson model that is fundamentally different from the linear case.