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arXiv · 1805.09438

Efficient side-coupling to photonic crystal nanobeam cavities via state-space overlap

Francis O. Afzal·Sami I. Halimi·Sharon M. Weiss
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Abstract

We present design guidelines for realizing side-coupled photonic crystal nanobeam (PCN) cavities with efficient coupling to low order resonances through adjusting the overlap of the PCN cavity mode and a feeding bus waveguide in both physical and k-space. We show that optimal side-coupled configurations function at a non-zero k-vector offset between the bus waveguide and PCN cavity modes. The straightforward design of side-coupled PCNs with high contrast resonances opens the door to their practical implementation in multiplexed, on-chip photonic devices.

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Francis O. Afzal, Sami I. Halimi, Sharon M. Weiss. 2018-05-23. Efficient side-coupling to photonic crystal nanobeam cavities via state-space overlap. https://doi.org/10.1364/josab.36.000585

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