Additive GaN Solid Immersion Lenses for Enhanced Photon Extraction Efficiency from Diamond Color Centers

• DOI: 10.1021/acsphotonics.3c00854
• Publication Date: 2023-08-30T15:42:53Z
• Authors: Xingrui Cheng; Nils Kolja Wessling; Saptarsi Ghosh; Andrew R. Kirkpat...; Menno J. Kappers; Yashna N. D. Lekhai; Gavin W. Morley; Rachel A. Oliver; Jason M. Smith; Martin D. Dawson; Patrick S. Salter; Michael J. Strain
• Keywords: Numerical aperture

Effective light extraction from optically active solid-state spin centers inside high-index semiconductor host crystals is an important factor in integrating these pseudo-atomic wider quantum systems. Here, we report increased fluorescent collection efficiency laser-written nitrogen-vacancy (NV) bulk diamond facilitated by micro-transfer printed GaN solid immersion lenses. Both laser-writing of NV and transfer printing micro-lens structures are compatible with high spatial resolution, enabling deterministic fabrication routes toward future scalable systems development. The micro-lenses integrated a noninvasive manner, as they added on top the unstructured surface bonded van der Waals forces. For emitters at 5 μm depth, find approximately 2× improvement using air objective numerical aperture NA = 0.95 good agreement simulations. Similarly, lenses strongly enhance when 0.5, significantly improving signal-to-noise ratio center emission while maintaining NV's properties after integration.