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arXiv · 2007.11463

Cross-polarization effects in sheared 2D grating couplers in a photonic BiCMOS technology

Galina Georgieva·Karsten Voigt·Christian Mai·Pascal M. Seiler·Klaus Petermann·Lars Zimmermann
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Abstract

We investigate numerically and experimentally sheared 2D grating couplers in a photonic BiCMOS technology with a focus on their splitting behavior. Two realization forms of a waveguide-to-grating shear angle are considered. The cross-polarization used as a figure-of-merit is shown to be strongly dependent on the grating perturbation strength and is a crucial limitation not only for the grating splitting performance, but also for its coupling efficiency.

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Galina Georgieva, Karsten Voigt, Christian Mai, Pascal M. Seiler, Klaus Petermann, Lars Zimmermann. 2020-07-22. Cross-polarization effects in sheared 2D grating couplers in a photonic BiCMOS technology. https://doi.org/10.35848/1347-4065%2Fab8e21

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