title: Transverse modulational instabilities of counterpropagating solitons in photorefractive crystals.
abstract: We study numerically the counterpropagating vector solitons in SBN:60 photorefractive crystals. A simple theory is provided for explaining the symmetry-breaking transverse instability of these solitons. Phase diagram is produced that depicts the transition from stable counterpropagating solitons to bidirectional waveguides to unstable optical structures. Numerical simulations are performed that predict novel dynamical beam structures, such as the standing-wave and rotating multipole vector solitonic clusters. For larger coupling strengths and/or thicker crystals the beams form unstable self-trapped optical structures that have no counterparts in the copropagating geometry.
authors.forename: M
authors.initials: M
authors.lastname: Belić
authors.forename: M
authors.initials: M
authors.lastname: Petrović
authors.forename: D
authors.initials: D
authors.lastname: Jović
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Strinic
authors.forename: D
authors.initials: D
authors.lastname: Arsenović
authors.forename: K
authors.initials: K
authors.lastname: Motzek
authors.forename: F
authors.initials: F
authors.lastname: Kaiser
authors.forename: Ph
authors.initials: P
authors.lastname: Jander
authors.forename: C
authors.initials: C
authors.lastname: Denz
authors.forename: M
authors.initials: M
authors.lastname: Tlidi
authors.forename: Paul
authors.initials: P
authors.lastname: Mandel