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Dr. Dr. Jens Simon
Phone: +49 531 592-3005
Email:
jens.simon(at)ptb.de
In quantum communication systems, the precise estimation of the detector´s response to the incoming light is necessary to avoid security breaches. The typical working regime uses a free-running single-photon avalanche diode in combination with attenuated laser pulses at telecom wavelength for encoding information. We demonstrate the validity of an analytical model for this regime which considers the effects of dark counts and dead time on the measured count rate. For the purpose of gaining a better understanding of these effects, the photon detections were separated from the dark counts via a software-induced gating mechanism. The model was verified by experimental data for mean photon numbers covering three orders of magnitude as well as for laser repetition frequencies below and above the inverse dead time. Consequently, our model would be of interest for predicting the detector response not only in the field of quantum communications, but also in any other quantum physics experiment where high detection rates are needed.
Authors:
Georgieva, Hristina; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Meda, Alice; Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 91, I-10135 Torino, Italy
M. F. Raupach, Sebastian; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Hofer, Helmuth; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Gramegna, Marco; Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 91, I-10135 Torino, Italy
Pietro Degiovanni, Ivo; Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 91, I-10135 Torino, Italy; Istituto Nazionale di Fisica Nucleare (INFN), Sezione Torino, Via Giuria 1, I-10125 Torino, Italy
Genovese, Marco; Istituto Nazionale di Ricerca Metrologica (INRIM), Strada delle Cacce 91, I-10135 Torino, Italy; Istituto Nazionale di Fisica Nucleare (INFN), Sezione Torino, Via Giuria 1, I-10125 Torino, Italy
López, Marco; 4.5, Angewandte Radiometrie, PTB-Braunschweig
Kück, Stefan; 4, Optik, PTB-Braunschweig
Dr. Dr. Jens Simon
Phone: +49 531 592-3005
Email:
jens.simon(at)ptb.de
Karin Conring
Phone: +49 531 592-3006
Fax: +49 531 592-3008
Email:
karin.conring(at)ptb.de
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