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arXiv · 0806.2742

Nonlinear switching of low-index defect modes in photonic lattices

Fangwei Ye·Yaroslav V. Kartashov·Victor A. Vysloukh·Lluis Torner
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Abstract

We address nonlinear signal switching between two low-index defect channels induced in periodic optical lattices. In contrast to conventional directional couplers, where the guiding mechanism is total internal reflection or refraction, in such Bragg-type coupler, the guidance is of a photonic-bandgap origin. The coupling length in the low-index coupler is controlled by the lattice parameters and by the channel spacing. In the nonlinear regime the Bragg-type coupler behaves as an all-optical switch, exhibiting a remarkable difference of switching power for focusing versus defocusing nonlinearity.

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Fangwei Ye, Yaroslav V. Kartashov, Victor A. Vysloukh, Lluis Torner. 2008-06-17. Nonlinear switching of low-index defect modes in photonic lattices. https://doi.org/10.1103/physreva.78.013847

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