Electronic and nuclear solid-state spins constitute another material platform for quantum information and quantum sensing. In particular, optically active spins in diamond-based nitrogen-vacancy (NV) centers constitute a unique testbed for technologies such as quantum registers, quantum memories and nanoscale magnetometers. Single electron spins in NV centers can be coherently manipulated by microwave excitation at room temperature and allow an optical initialization and readout.
The optical readout is possible thanks to a spin-dependent fluorescence brightness produced by the NV centers. Its sensitivity is primarily limited by the gathered fluorescence intensity and the brightness contrast between the spin states (the spin contrast). Nanophotonics suggests promising methods to increase the fluorescence brightness of NV centers and improve the sensitivity of the spin readout for a variety of applications.
In the past, we have studied the influence of nanophotonic environment on the spin contrast in NV ensembles . We have observed spin-dependent fluorescence signal from plasmon-enhanced NV centers . We have also realized an interface for the optical collection and microwave signal delivery to NV centers based on a single multi-functional metallic layer . We now aim at designing and realizing on-chip nanophotonic and nanomagnetic interfaces that can increase spin readout sensitivity and harness the interaction between distant spins.
 S. Bogdanov, M.Y. Shalaginov, P. Kapitanova, J. Liu, M. Ferrera, A. Lagutchev, P. Belov, J. Irudayaraj, A. Boltasseva and V. Shalaev, Physical Review B 96, 035146 (2017)
 S.I. Bogdanov, O.A. Makarova, A.S. Lagutchev, D. Shah, C.-C. Chiang, S. Saha, A.S. Baburin, I.A. Ryzhikov, I.A. Rodionov, A.V. Kildishev, A. Boltasseva and V.M. Shalaev, preprint available on arXiv at http://arxiv.org/abs/1902.05996
 M. Y. Shalaginov, S. I. Bogdanov, A. S. Lagutchev, A. V. Kildishev, A. Boltasseva, and V. M. Shalaev, ACS Photonics 7, 2018 (2020)