3D-Printed Assembly Including Micro-Optics for Efficient Direct Light Coupling

Quantum defects in silicon carbide (SiC), which can be created with femtosecond laser irradiation, provide enormous potential for applications in quantum communication, quantum computing, and quantum sensing [1]. SiC features several optically active point defects with optically addressable spin states [2] across the visible to near infrared spectral range. However, for delivering light to-and from these positions, precise alignment and collection mechanism for maximizing efficiency is essential. Among other methods, light delivery through optical fibres provides high coupling efficiency and robustness, however, it requires precision alignment. For fiber to the quantum device assembly, printed docking structures for optical fibres at the desired defect positions has been reported previously [3]. However, bonding optical fiber onto the docking structure provides robust coupling, but only low optical coupling efficiency, which is especially important for collecting light from embedded defects. Efficiency can be improved, by including micro-optics directly into the docking structure.