Dissipative defect modes in periodic structures

We show that periodic optical lattices imprinted in cubic nonlinear media with strong two-photon absorption and localized linear gain landscapes support stable dissipative defect modes in both focusing and defocusing media. Their shapes and transverse extent are determined by the propagation constant that belongs to a gap of the lattice spectrum, which, in turn, is determined by the relation between gain and losses. One-hump and two-hump dissipative defect modes are obtained. (C) 2010 Optical Society of America