2021/05/05 by Liangwei Zeng, Vladimir V. Konotop, Xiaowei Lu +3 · 1 citation
Physics and Astronomy · #nlin.PS #physics.optics
paper · pdf · doi:10.1364/ol.424389
published as Opt. Lett. 46(9), 2216-2219 (2021) · published in Optics Letters
arxiv created 2021/05/05 · arxiv updated 2021/11/02
Dark solitons and localized defect modes against periodic backgrounds are considered in arrays of waveguides with defocusing Kerr nonlinearity constituting a nonlinear lattice. Bright defect modes are supported by local increase of the nonlinearity, while dark defect modes are supported by a local decrease of the nonlinearity. Dark solitons exist for both types of the defect, although in the case of weak nonlinearity they feature side bright humps making the total energy propagating through the system larger than the energy transferred by the constant background. All considered defect modes are found stable. Dark solitons are characterized by relatively narrow windows of stability. Interactions of unstable dark solitons with bright and dark modes are described.