Bright single-photon emission from a GeV center in diamond under a microfabricated solid immersion lens at room temperature

authored by
J. Christinck, F. Hirt, H. Hofer, Z. Liu, M. Etzkorn, T. Dunatov, M. Jakšić, J. Forneris, S. Kück

We report on the metrological characterization of the emission from a germanium-vacancy center in diamond under a microfabricated solid immersion lens in a confocal laser-scanning microscope setup. Ge ions were implanted into a synthetic diamond at 3 MeV, and germanium-vacancy centers were then formed by subsequent annealing. Afterward, solid immersion lenses were fabricated in a focused ion beam scanning electron microscope. The photoluminescence was investigated at room temperature in terms of the spectral distribution, the excited state lifetime, the second-order correlation function, and the saturation behavior, proving simultaneous high single-photon purity and high brightness. Two methods were exploited to minimize the residual multi-photon probability: spectral filtering and temporal filtering. According to these results, we assume that Raman scattered photons and emission from neighboring color centers play an important role in the residual multi-photon emission probability. The system efficiency of the single-photon source was investigated and found to be in accordance with the value calculated from all sources of loss in the setup. The branching ratio of the germanium-vacancy center for the decay into the ground state and into metastable state was calculated. The results enable the usage of the single-photon source in future quantum radiometric experiments.

External Organisation(s)
National Metrology Institute of Germany (PTB)
Technische Universität Braunschweig
Ruder Boskovic Institute
University of Turin
Journal of applied physics
Publication date
Publication status
Peer reviewed
ASJC Scopus subject areas
Physics and Astronomy(all)
Electronic version(s) (Access: Open)