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Spatial-Spectral Vortex Solitons in Quadratic Lattices

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 نشر من قبل Zhiyong Xu
 تاريخ النشر 2009
  مجال البحث فيزياء
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We predict the existence of spatial-spectral vortex solitons in one-dimensional periodic waveguide arrays with quadratic nonlinear response. In such vortices the energy flow forms a closed loop through the simultaneous effects of phase gradients at the fundamental frequency and second-harmonic fields, and the parametric frequency conversion between the spectral components. The linear stability analysis shows that such modes are stable in a broad parameter region.



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