Self-induced gap solitons

Abstract
It is shown that in nonlinear discrete systems localized modes may exist in the form of self-induced gap solitons. Such structures appear due to a nonlinearity-induced gap in the cw spectrum, when one group of particles in the lattice plays a role of an effective periodic potential to other particles supporting a spatially localized oscillation. Two examples are considered and exact soliton solutions describing this type of localized modes are presented.