  We consider a system of two or four nonlinear sites coupled with binary chain
waveguides. When a monochromatic wave is injected into the first (symmetric)
propagation channel the presence of cubic nonlinearity can lead to symmetry
breaking giving rise to emission of antisymmetric wave into the second
(antisymmetric) propagation channel of the waveguides. We found that in the
case of nonlinear plaquette there is a domain in the parameter space where
neither symmetry preserving nor symmetry breaking stable stationary solutions
exit. As a result injection of a monochromatic symmetric wave gives rise to
emission of nonsymmetric satellite waves with energies different from the
energy of the incident wave. Thus, the response exhibits nonmonochromatic
behavior.
