Nodal solitons and the nonlinear breaking of discrete symmetry
  We present a new type of soliton solutions in nonlinear photonic systems with discrete point-symmetry. These solitons have their origin in a novel mechanism of breaking of discrete symmetry by the presence of nonlinearities. These so-called nodal solitons are characterized by nodal lines determined by the discrete symmetry of the system. Our physical realization of such a system is a 2D nonlinear photonic crystal fiber owning C6v symmetry. 
A. Ferrando, M. Zacares, P. Andres, P. Fernandez de Cordoba and J.A.   Monsoriu