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Adjoint-optimized nanoscale light extractor for nitrogen-vacancy centers in diamond

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 نشر من قبل Mikhail Kats
 تاريخ النشر 2020
  مجال البحث فيزياء
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We designed a nanoscale light extractor (NLE) for efficient outcoupling and beaming of broadband light emitted by shallow, negatively charged nitrogen-vacancy (NV) centers in bulk diamond. The NLE consists of a patterned silicon layer on diamond and requires no etching of the diamond surface. Our design process is based on adjoint optimization using broadband time-domain simulations and yields structures that are inherently robust to positioning and fabrication errors. Our NLE functions like a transmission antenna for the NV center, enhancing the optical power extracted from an NV center positioned 10 nm below the diamond surface by a factor of more than 35, and beaming the light into a +/-30{deg} cone in the far field. This approach to light extraction can be readily adapted to other solid-state color centers.



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