Recent activities on the metrological realization of an absolute single-photon source based on a nitrogen-vacancy center in nanodiamond.

Single-photon sources play an important role in several fields of research, e.g. in quantum key distribution and quantum-enhanced measurements. In radiometry, a single-photon source is very favorable, compared to a classical source, as a standard source for the detection efficiency calibration of single-photon detectors. Furthermore, such source is necessary to close the gap between classical and quantum radiometry, i.e. for the direct comparison between classical analogue detectors and single-photon detectors. We present the metrological realization of an absolute single-photon source based on a nitrogen-vacancy (NV-) center in nanodiamond, which is under development at the Physikalisch-Technische Bundesanstalt (PTB), the German national metrology institute. This source is traceable to national standards for optical radiant power and spectral power distribution via an unbroken chain in terms of its absolute spectral photon flux per wavelength and absolute spectral radiant flux per wavelength. This investigation includes a full determination of the measurement uncertainty. Besides this, we calculated the angular emission behavior of such a NV-center and compared the results with the measurement of the angle-dependent emission of an NV-center in nanodiamond.

Rodiek, Beatrice; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Christinck, Justus; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Hofer, Helmuth; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Georgieva, Hristina; 4.5, Angewandte Radiometrie, PTB-Braunschweig
López, Marco; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Kück, Stefan; 4, Optik, PTB-Braunschweig