title: Self-trapping of optical vortices in waveguide lattices with a self-defocusing nonlinearity.
abstract: We demonstrate the self-trapping of single- and double-charged optical vortices in waveguide lattices induced with a self-defocusing nonlinearity. Under appropriate conditions, a donut-shaped single-charged vortex evolves into a stable discrete gap vortex soliton, but a double-charged vortex turns into a self-trapped quadrupole-like structure. Spectrum measurement and numerical analysis suggest that the gap vortex soliton does not bifurcate from the edge of the Bloch band, quite different from previously observed gap spatial solitons. Our numerical findings are in good agreement with experimental observations.
authors.affiliation: The Key Laboratory of Weak-Light Nonlinear Photonics, Ministry of Education and TEDA Applied Physical School, Nankai University, Tianjin 300457, China.
authors.forename: Daohong
authors.initials: D
authors.lastname: Song
authors.forename: Cibo
authors.initials: C
authors.lastname: Lou
authors.forename: Liqin
authors.initials: L
authors.lastname: Tang
authors.forename: Xiaosheng
authors.initials: X
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Xingyu
authors.initials: X
authors.lastname: Chen
authors.forename: Kody J H
authors.initials: KJ
authors.lastname: Law
authors.forename: Hadi
authors.initials: H
authors.lastname: Susanto
authors.forename: P G
authors.initials: PG
authors.lastname: Kevrekidis
authors.forename: Jingjun
authors.initials: J
authors.lastname: Xu
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Chen
mesh_terms: D003198:Computer Simulation; D007368:Interferometry / Q000295:instrumentation / Q000379:methods; D008027:Light; D008962:Models, Theoretical; D016011:Normal Distribution; D055095:Optics and Photonics; D010825:Physics / Q000379:methods; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D013997:Time Factors