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arXiv · 2410.12150

Triangular cross-section grating couplers for integrated quantum nanophotonic hardware in silicon carbide

Pranta Saha·Alex H. Rubin·Sridhar Majety·Scott Dhuey·Marina Radulaski
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Abstract

We design, fabricate, and characterize fishbone grating couplers for triangular cross-section photonics in silicon carbide compatible with color center integration. The periodic and aperiodic grating coupler designs are optimized to outcouple up to 31% of light in the fundamental TE mode of a triangular waveguide. The devices are fabricated using an ion beam etching process in a 4H-SiC sample implanted with NV center ensembles. The room-temperature transmission and the cryogenic NV center photoluminescence collection measurements indicate experimental grating coupler efficiency of up to 24%. This result provides a scalable method to efficiently extract color center light from SiC quantum nanophotonic devices to free-space optics.

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Pranta Saha, Alex H. Rubin, Sridhar Majety, Scott Dhuey, Marina Radulaski. 2025-04-23. Triangular cross-section grating couplers for integrated quantum nanophotonic hardware in silicon carbide. https://arxiv.org/abs/2410.12150

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