Enhanced photon extraction via cone structured waveguide from nitrogen vacancy center in diamond

• Published in: Results in optics Vol. 13; p. 100535
• Main Authors: Priyadarshini, V., Dharani, A., Roy, Subhankar, Hu, Jianping, Ummal Momeen, M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-12-2023; Elsevier
• Subjects: Collection efficiency; NV center in diamond; Zero phonon line; Collection efficiency; Zero phonon line; NV center in diamond
• ISSN: 2666-9501; 2666-9501
• DOI: 10.1016/j.rio.2023.100535

We present a novel design of optical nanostructure for efficient light extraction from nitrogen vacancy (NV) center in diamond. Numerical simulations of the optimal structure exhibit significant collection efficiency along with a stable radiation profile. We achieved a photon collection efficiency of 70% even with a lower numerical aperture of 0.5. Two different approaches (simple cone and encapsulated cone) have been adopted to reach a high geometrical tolerance without affecting much to the efficiency and emission profile. Besides that, our structure adds an extra benefit in terms of emission enhancement near zero phonon line (ZPL) region of NV spectra. Overall, this cone shaped diamond structure provides a robust, highly efficient and directional emission which can be integrated with a quantum optical network for various applications.