Southwest Quantum Information and Technology

Enhanced emission of zero-phonon line photons from a single nitrogen-vacancy center in diamond

Presenting Author: Michael Gould, Fu group (Washington)
Contributing Author(s): Srivatsa Chakravarthi, Ian R. Christen, Shabnam Dadgostar, Fariba Hatami, Kai-Mei Fu

We demonstrate efficient, resonantly enhanced collection of zero-phonon line (ZPL) photons from a single nitrogen-vacancy (NV) center in diamond. The near-surface NV center is optically coupled to an integrated gallium-phosphide-on-diamond (GaP-on-diamond) disk resonator, which is coupled to an output bus waveguide. We estimate a total collection rate of 3.2 x 10^5 ZPL photons into the bus waveguide. This corresponds to a quantum efficiency of approximately 4.5%, significantly higher than the 3% theoretical limit without the use of resonant enhancement. The device was fabricated on a GaP-on-diamond chip, alongside a large number of other integrated photonic devices. These include vertical grating couplers with average coupling efficiencies of 17%, low-loss single-mode waveguides and low-loss directional couplers. This work puts the platform in a strong position to enable fully integrated NV-NV entanglement generation, at rates several orders of magnitude larger than what has been demonstrated in literature.

(Session 13 : Saturday from 3:15 pm - 3:45 pm)