PT Journal
AU Kitaygorsky, J
   Zhang, J
   Verevkin, A
   Sergeev, A
   Korneev, A
   Matvienko, V
   Kouminov, P
   Smirnov, K
   Voronov, B
   Gol'tsman, G
   Sobolewski, R
TI Origin of dark counts in nanostructured NbN single-photon detectors
SO IEEE Trans. Appl. Supercond.
JI IEEE Trans. Appl. Supercond.
PY 2005
BP 545
EP 548
VL 15
IS 2
DI 10.1109/TASC.2005.849914
DE SSPD dark counts; SNSPD; dark counts rate
AB We present our study of dark counts in ultrathin (3.5 to 10 nm thick), narrow (120 to 170 nm wide) NbN superconducting stripes of different lengths. In experiments, where the stripe was completely isolated from the outside world and kept at temperature below the critical temperature Tc, we detected subnanosecond electrical pulses associated with the spontaneous appearance of the temporal resistive state. The resistive state manifested itself as generation of phase-slip centers (PSCs) in our two-dimensional superconducting stripes. Our analysis shows that not far from Tc, PSCs have a thermally activated nature. At lowest temperatures, far below Tc, they are created by quantum fluctuations.
ER