Belić M, Jović D, Prvanović S, Arsenović D, Petrović M
Opt Express. 2006 Jan 23;14(2):794-9. doi: 10.1364/opex.14.000794.
Dynamical properties of counterpropagating (CP) mutually incoherent self-trapped beams in optically induced photonic lattices are investigated numerically. A local model with saturable Kerr-like nonlinearity is adopted for the photorefractive media, and an optically generated two-dimensional fixed photonic lattice introduced in the crystal. Different incident beam structures are considered, such as Gaussians and vortices of different topological charge. We observe spontaneous symmetry breaking of the head-on propagating Gaussian beams as the coupling strength is increased, resulting in the splitup transition of CP components. We see discrete diffraction, leading to the formation of discrete CP vector solitons. In the case of vortices, we find beam filamentation, as well as increased stability of the central vortex ring. A strong pinning of filaments to the lattice sites is noted. The angular momentum of vortices is not conserved, either along the propagation direction or in time, and, unlike the case without lattice, the rotation of filaments is not as readily observed.
对光学诱导光子晶格中反向传播（CP）的相互非相干自陷光束的动力学特性进行了数值研究。采用具有可饱和类克尔非线性的局部模型来描述光折变介质，并在晶体中引入光学产生的二维固定光子晶格。考虑了不同的入射光束结构，如不同拓扑电荷的高斯光束和涡旋光束。我们观察到，随着耦合强度的增加，正向传播的高斯光束会发生自发对称性破缺，导致CP分量的分裂转变。我们还看到了离散衍射，从而形成了离散的CP矢量孤子。在涡旋光束的情况下，我们发现了光束丝状化以及中心涡旋环稳定性的增强。注意到细丝强烈地钉扎在晶格位点上。涡旋的角动量在传播方向上或随时间都不守恒，并且与没有晶格的情况不同，细丝的旋转不太容易观察到。
