PT Journal AU Divochiy, A Misiaszek, M Vakhtomin, Y Morozov, P Smirnov, K Zolotov, P Kolenderski, P TI Single photon detection system for visible and infrared spectrum range SO Opt. Lett. JI Opt. Lett. PY 2018 BP 6085 EP 6088 VL 43 IS 24 DI 10.1364/OL.43.006085 LA English AB We demonstrate niobium nitride based superconducting single-photon detectors sensitive in the spectral range 452-2300 nm. The system performance was tested in a real-life experiment with correlated photons generated by means of spontaneous parametric downconversion, where one photon was in the visible range and the other was in the infrared range. We measured a signal to noise ratio as high as 4x10(4) in our detection setting. A photon detection efficiency as high as 64% at 1550 nm and 15% at 2300 nm was observed. ER