title: Phase transitions of nonlinear waves in quadratic waveguide arrays.
abstract: We study two-color parametric nonlinear modes in waveguide arrays with a quadratic nonlinear response. We predict theoretically and observe experimentally a new type of phase transition manifested in an abrupt power-controlled change of the mode structure from unstaggered to staggered, due to the interplay of localization and synchronization in parametrically driven discrete systems.
authors.affiliation: Friedrich-Schiller-University Jena, Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Setzpfandt
authors.forename: Andrey A
authors.initials: AA
authors.lastname: Sukhorukov
authors.forename: Dragomir N
authors.initials: DN
authors.lastname: Neshev
authors.forename: Roland
authors.initials: R
authors.lastname: Schiek
authors.forename: Yuri S
authors.initials: YS
authors.lastname: Kivshar
authors.forename: Thomas
authors.initials: T
authors.lastname: Pertsch