Cavity-Enhanced Photon Emission from a Single Germanium-Vacancy Center in a Diamond Membrane
Rasmus Høy Jensen, Erika Janitz, Yannik Fontana, He Yi, Olivier Gobron, Ilya P. Radko, Mihir K. Bhaskar, Ruffin E. Evans, César Daniel Rodríguez Rosenblueth, Lilian Childress, Alexander Huck, Ulrik L. Andersen
Abstract
The nitrogen-vacancy center in diamond has been explored extensively as a light-matter interface for quantum information applications, however, it is limited by low coherent photon emission and spectral instability. Here, we present a promising interface based on an alternative defect with superior optical properties (the germanium-vacancy) coupled to a finesse-11 000 fiber cavity, resulting in a ${31}_{\ensuremath{-}15}^{+11}$-fold increase in the spectral density of zero-phonon-line emission. This work sets the stage for cryogenic experiments, where we predict a measurable increase in the spontaneous emission rate.