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arXiv · 1006.2093

Strongly enhanced photon collection from diamond defect centres under micro-fabricated integrated solid immersion lenses

J. P. Hadden·J. P. Harrison·A. C. Stanley-Clarke·L. Marseglia·Y-L. D. Ho·B. R. Patton·J. L. O'Brien·J. G. Rarity
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Abstract

The efficiency of collecting photons from optically active defect centres in bulk diamond is greatly reduced by refraction and reflection at the diamond-air interface. We report on the fabrication and measurement of a geometrical solution to the problem; integrated solid immersion lenses (SILs) etched directly into the surface of diamond. An increase of a factor of 10 was observed in the saturated count-rate from a single negatively charged nitrogen-vacancy (NV-) within a 5um diameter SIL compared with NV-s under a planar surface in the same crystal. A factor of 3 reduction in background emission was also observed due to the reduced excitation volume with a SIL present. Such a system is potentially scalable and easily adaptable to other defect centres in bulk diamond.

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J. P. Hadden, J. P. Harrison, A. C. Stanley-Clarke, L. Marseglia, Y-L. D. Ho, B. R. Patton, J. L. O'Brien, J. G. Rarity. 2010-06-11. Strongly enhanced photon collection from diamond defect centres under micro-fabricated integrated solid immersion lenses. https://doi.org/10.1063/1.3519847

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