@ARTICLE\{IMM2001-0166,
    author       = "A. A. Sukhorukov and Y. S. Kivshar and O. Bang and C. M. Soukoulis",
    title        = "Parametric localized modes in quadratic nonlinear photonic structures",
    year         = "2001",
    month        = "jan",
    pages        = "1-9/016615",
    journal      = "Physical Review E",
    volume       = "63",
    editor       = "",
    number       = "1",
    publisher    = "",
    url          = "http://www2.compute.dtu.dk/pubdb/pubs/166-full.html",
    abstract     = "We analyze two-color spatially localized nonlinear modes formed by parametrically coupled fundamental and second-harmonic fields excited at quadratic (or chi2) nonlinear interfaces embedded in a linear layered structure-a quadratic nonlinear photonic crystal. For a periodic lattice of nonlinear interfaces, we derive an effective discrete model for the amplitudes of the fundamental and second-harmonic waves at the interfaces (the so-called discrete chi2 equations) and find, numerically and analytically, the spatially localized solutions-discrete gap solitons. For a single nonlinear interface in a linear superlattice, we study the properties of two-color localized modes, and describe both similarities to and differences from quadratic solitons in homogeneous media."
}