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arXiv · 2104.08021

Efficient self-imaging grating couplers on a Lithium-Niobate-On-Insulator platform at near-visible and telecom wavelengths

Emma Lomonte·Francesco Lenzini·Wolfram H. P. Pernice
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Abstract

Lithium-Niobate-On-Insulator (LNOI) has emerged as a promising platform in the field of integrated photonics. Nonlinear optical processes and fast electro-optic modulation have been reported with outstanding performance in ultra-low loss waveguides. In order to harness the advantages offered by the LNOI technology, suitable fiber-to-chip interconnects operating at different wavelength ranges are demanded. Here we present easily manufacturable, self-imaging apodized grating couplers, featuring a coupling efficiency of the TE0 mode as high as $\simeq 47.1\%$ at $\lambda$=1550 nm and $\simeq 44.9\%$ at $\lambda$=775 nm. Our approach avoids the use of any metal back-reflector for an improved directivity or multi-layer structures for an enhanced grating strength.

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Emma Lomonte, Francesco Lenzini, Wolfram H. P. Pernice. 2021-04-16. Efficient self-imaging grating couplers on a Lithium-Niobate-On-Insulator platform at near-visible and telecom wavelengths. https://doi.org/10.1364/oe.428138

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