Higher-order vortex solitons, multipoles, and supervortices on a square optical latticeH. Sakaguchi1 and B. A. Malomed2
1 Department of Applied Science for Electronics and Materials Interdisciplinary Graduate School of Engineering Sciences Kyushu University - Kasuga, Fukuoka 816-8580, Japan
2 Department of Interdisciplinary Studies School of Electrical Engineering, Faculty of Engineering Tel Aviv University - Tel Aviv 69978, Israel
received 4 April 2005; accepted in final form 29 September 2005
published online 26 October 2005
We predict new generic types of vorticity-carrying soliton complexes in a class of physical systems including an attractive Bose-Einstein condensate in a square optical lattice (OL) and photonic lattices in photorefractive media. The patterns include ring-shaped higher-order vortex solitons and supervortices. Stability diagrams for these patterns, based on direct simulations, are presented. The vortex ring solitons are stable if the phase difference between adjacent solitons in the ring is larger than , while the supervortices are stable in the opposite case, . A qualitative explanation to the stability is given.
03.75.Lm - Tunneling, Josephson effect, Bose-Einstein condensates in periodic potentials, solitons, vortices, and topological excitations.
05.45.Yv - Solitons.
42.65.Tg - Optical solitons; nonlinear guided waves.
© EDP Sciences 2005