%0 Journal Article
%T VIZIBLE SPECTRUM SINGLE PHOTON DETECTION MODULE
%A ALEXANDRU RUSU
%A LUCIAN RUSU
%A ANCA BELDICEANU
%A CONSTANTIN T£¿RC£¿
%J Journal of Science and Arts
%D 2010
%I Bibliotheca Publishing House
%X Experiments using entangled photons and their applications require the detection of extremely weak light beams: the incoming photons arrive to the detector one at a time.Visible spectrum single photon detection is a challenging problem because the photon energy can produce only one electron-hole pair and such a signal is less than the sum of the intrinsic noise of the semiconductor detector and the associated electronics. Nevertheless, a free electron can initiate an avalanche discharge within an avalanche photodiode (APD), reversely polarized at a value slightly higher than its breakdown voltage. The discharge quenching and the restoration of the APD voltage are necessary to enable another photon detection.The module we are talking about is using both the passive quenching ¨C to limit the discharge current to small enough values, considered safe ¨C and the active quenching ¨C to increase the upper margin of the measuring range to values as high as 1,¡­ 1.5 mega pulses per second.Some major technical problems we have dealt with, to create a single photon detection module are presented:- APD equivalent dynamic resistor evaluation;- shielding against background light;- controlling the APD working temperature.A selected list of module measured characteristics concludes the presentation.
%K single photon counting
%U http://www.icstm.ro/DOCS/josa/josa_2010_1/c.06_vizible_spectrum_single_photon_detection_module.pdf