Enhanced emission extraction and selective readout of NV centers with   all-dielectric nanoantennas
  We propose a novel approach to facilitate a readout processes of isolated negatively charged nitrogen-vacancy (NV) centers based on the concept of all-dielectric nanoantennas. We reveal that all-dielectric nanoantenna can significantly enhance both the emission rate and emission extraction efficiency of a photoluminescence signal from a single NV center in a diamond nanoparticle placed on a dielectric substrate. We prove that the proposed approach provides high directivity, large Purcell factor, and efficient beam steering, thus allowing an efficient far-field initialization and readout of several NV centers separated by subwavelength distances. 
Alexander E. Krasnok, Alex Maloshtan, Dmitry N. Chigrin, Yuri S.   Kivshar, Pavel A. Belov
physics.optics