{ "id": "1411.5582", "version": "v1", "published": "2014-11-20T15:56:52.000Z", "updated": "2014-11-20T15:56:52.000Z", "title": "Ground states of a system of nonlinear Schrödinger equations with periodic potentials", "authors": [ "Jarosław Mederski" ], "categories": [ "math.AP", "math-ph", "math.MP" ], "abstract": "We are concerned with a system of coupled Schr\\\"odinger equations $$-\\Delta u_i + V_i(x)u_i = \\partial_{u_i}F(x,u)\\hbox{ on }\\mathbb{R}^N,\\,i=1,2,...,K,$$ where $F$ and $V_i$ are periodic in $x$ and $0$ belongs to a spectral gap of the Schr\\\"odinger operator $-\\Delta+V_i(x)$ for any $i=1,2,...,K$. The problem appears in nonlinear optics, where gap solitons in photonic crystals are studied. Photonic crystals have a periodic nanostructure and the term $F$ is due to the presence of nonlinear polarization. General assumptions on $F$ are imposed and we find a ground state solution being a minimizer of the energy functional associated with the system on a Nehari-Pankov manifold. If $0$ lies below all the spectra $\\sigma(-\\Delta+V_i)$ we admit a sign-changing behaviour of $F$ and we are able to treat problems with the mixture of self-focusing and defocusing nonlinearties. Our approach is based on a new linking-type result involving the Nehari-Pankov manifold.", "revisions": [ { "version": "v1", "updated": "2014-11-20T15:56:52.000Z" } ], "analyses": { "subjects": [ "35Q60", "35J20", "35Q55", "58E05", "35J47" ], "keywords": [ "nonlinear schrödinger equations", "periodic potentials", "photonic crystals", "nehari-pankov manifold", "ground state solution" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1411.5582M" } } }