PT Journal
AU Korneev, A
   Minaeva, O
   Rubtsova, I
   Milostnaya, I
   Chulkova, G
   Voronov, B
   Smirnov, K
   Seleznev, V
   Gol'tsman, G
   Pearlman, A
   Slysz, W
   Cross, A
   Alvarez, P
   Verevkin, A
   Sobolewski, R
TI Superconducting single-photon ultrathin NbN film detector
SO Quantum Electronics
PY 2005
BP 698
EP 700
VL 35
IS 8
DI 10.1070/QE2005v035n08ABEH009152
DE NbN SSPD; SNSPD
AB Superconducting single-photon ultrathin NbN film detectors are studied. The development of manufacturing technology of detectors and the reduction of their operating temperature down to 2 K resulted in a considerable increase in their quantum efficiency, which reached in the visible region (at 0.56 μm) 30%—40%, i.e., achieved the limit determined by the absorption coefficient of the film. The quantum efficiency exponentially decreases with increasing wavelength, being equal to ~20% at 1.55 μm and ~0.02% at 5 μm. For the dark count rate of ~10-4s-1, the experimental equivalent noise power was 1.5×10-20 W Hz-1/2; it can be decreased in the future down to the record low value of 5×10-21 W Hz-1/2. The time resolution of the detector is 30 ps.
ER