Modulational instability in nonlinear periodic structures: Implications for ‘‘gap solitons’’

A nonlinear periodic structure can convert an input continuous wave beam into a train of pulses. This modulational instability implies that the nonlinear spatial resonance (‘‘gap solitons’’) of distributed feedback structures are generally unstable. Stability is assured only for low coupling strengths or large detunings from the Bragg condition.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70181/2/APPLAB-58-10-1001-1.pd