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

Journal Article · Tue Jul 01 00:00:00 EDT 2025 · APL Materials

DOI:https://doi.org/10.1063/5.0244038· OSTI ID:2583661

Saha, Pranta; Rubin, Alex H; Majety, Sridhar; Dhuey, Scott; Radulaski, Marina

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.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: US Department of Energy; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22), Scientific User Facilities Division (SC-22.3 )
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 2583661
• Journal Information: APL Materials, Journal Name: APL Materials Journal Issue: 7 Vol. 13
• Country of Publication: United States
• Language: English