Coupling diamond defect centers to Fabry-Perot microcavities

Yannick Dumeige, Romain Alléaume, Philippe Grangier +2 more

Bryan J. Dalton, M. Babiker, P. L. Knight

Jenna Hagemeier, Toeno van der Sar, Susanna M. Thon +8 more

Florian Feuchtmayr, Robert Berghaus, Selene Sachero +6 more

Color centers in diamond, among them the negatively charged germanium vacancy (GeV−), are promising candidates for many applications of quantum optics, such as a quantum network. For efficient implementation, the optical transitions need to be coupled to a single optical mode. Here, we demonstrate the transfer of a nanodiamond containing a single ingrown GeV− center with excellent optical properties to an open Fabry–Pérot microcavity by nanomanipulation utilizing an atomic force microscope. Coupling of the GeV− defect to the cavity mode is achieved, while the optical resonator maintains a high finesse of F=7700, and a 48-fold spectral density enhancement is observed. This article demonstrates the integration of a GeV− defect with a Fabry–Pérot microcavity under ambient conditions with the potential to extend the experiments to cryogenic temperatures toward an efficient spin-photon platform.

Daniel Riedel, Immo Söllner, Brendan Shields +5 more

Nitrogen-vacancy centers---a type of atom-sized defect in diamonds---have potential for use as quantum bits in quantum information technologies. However, low rates of entanglement between the defect spin and the photons they produce hamper the mediation of long-distance connections. A new experiment shows a way around this limitation by employing a tunable, miniaturized Fabry-P\'erot microcavity.

Robert Berghaus, Gregor W. Bayer, Selene Sachero +4 more

Color centers in diamond, including defects like silicon vacancy and germanium vacancy, offer optical accessibility and spin transition for quantum bits. Our investigation focuses on integrating diamond into optical microcavities to enhance the signal and enable fast quantum communication.