title: Two-dimensional solitons in quasi-phase-matched quadratic crystals.
abstract: We study the existence and dynamics of two-dimensional spatial solitons in crystals that exhibit a periodic modulation of both the refractive index and the second-order susceptibility for achieving quasi-phase-matching. Far from resonances between the domain length of the periodic crystal and the diffraction length of the beams, it is demonstrated that the properties of the solitons in this quasi-phase-matched geometry are strongly influenced by the induced third-order nonlinearities. The stability properties of the two-dimensional solitons are analyzed as a function of the total power, the effective wave-vector mismatch between the first and second harmonics, and the relative strength between the induced third-order nonlinearity and the effective second-order nonlinearity. Finally, the formation of two-dimensional solitons from a Gaussian beam excitation is investigated numerically.
authors.affiliation: Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA.
authors.forename: N-C
authors.initials: NC
authors.lastname: Panoiu
authors.forename: D
authors.initials: D
authors.lastname: Mihalache
authors.forename: D
authors.initials: D
authors.lastname: Mazilu
authors.forename: F
authors.initials: F
authors.lastname: Lederer
authors.forename: R M
authors.initials: RM
authors.lastname: Osgood