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arXiv · 2307.00916

Enhanced Spectral Density of a Single Germanium Vacancy Center in a Nanodiamond by Cavity-Integration

Florian Feuchtmayr·Robert Berghaus·Selene Sachero·Gregor Bayer·Niklas Lettner·Richard Waltrich·Patrick Maier·Viatcheslav Agafonov·Alexander Kubanek
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Abstract

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 = 7,700 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 towards an efficient spin-photon platform.

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Florian Feuchtmayr, Robert Berghaus, Selene Sachero, Gregor Bayer, Niklas Lettner, Richard Waltrich, Patrick Maier, Viatcheslav Agafonov, Alexander Kubanek. 2023-11-30. Enhanced Spectral Density of a Single Germanium Vacancy Center in a Nanodiamond by Cavity-Integration. https://doi.org/10.1063/5.0156787

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