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arXiv · 1308.5862

Actively coupled optical waveguides

N. V. Alexeeva·I. V. Barashenkov·K. Rayanov·S. Flach
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Abstract

We consider light propagation through a pair of nonlinear optical waveguides with absorption, placed in a medium with power gain. The active medium boosts the in-phase component of the overlapping evanescent fields of the guides, while the nonlinearity of the guides couples it to the damped out-of-phase component creating a feedback loop. As a result, the structure exhibits stable stationary and oscillatory regimes in a wide range of gain-loss ratios. We show that the pair of actively-coupled ($\mathcal{AC}$) waveguides can act as a stationary or integrate-and-fire comparator sensitive to tiny differences in their input powers.

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N. V. Alexeeva, I. V. Barashenkov, K. Rayanov, S. Flach. 2013-08-27. Actively coupled optical waveguides. https://doi.org/10.1103/physreva.89.013848

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