title: Competing nonlinearities in quadratic nonlinear waveguide arrays.
abstract: We demonstrate experimentally the existence of competing focusing and defocusing nonlinearities in a double-resonant system with quadratic nonlinear response. We use an array of periodically poled coupled optical waveguides and observe inhibition of the nonlinear beam self-action independent on power. This inhibition is demonstrated in both regimes of normal and anomalous beam diffraction.
authors.affiliation: Friedrich-Schiller-University Jena, Max-Wien-Platz 1, 07743 Jena, Germany. f.setzpfandt@uni-jena.de
authors.forename: Frank
authors.initials: F
authors.lastname: Setzpfandt
authors.forename: Dragomir N
authors.initials: DN
authors.lastname: Neshev
authors.forename: Roland
authors.initials: R
authors.lastname: Schiek
authors.forename: Falk
authors.initials: F
authors.lastname: Lederer
authors.forename: Andreas
authors.initials: A
authors.lastname: Tünnermann
authors.forename: Thomas
authors.initials: T
authors.lastname: Pertsch