The limitation of noise equivalent power by background radiation for
infrared superconducting single photon detectors coupled to standard
single mode optical fibers
K. Smirnov 1,2,3, Y. Vachtomin 1,2, A. Divochiy
2, A. Antipov 2, G. Goltsman 1,2,3
1
Moscow State Pedagogical University
2
CJSC “Superconducting nanotechnology” (Scontel)
3
National Research University Higher School of Economics
The paper is
received on April 20, 2015
Abstract.
We investigated the minimum level of the
dark count rates and noise equivalent power of superconducting single photon detectors
coupled to standard single mode optical fibers. We found that background
radiation limits the minimum level of the dark count rates. We also proposed
the effective method for reducing background radiation out of the required
spectral range of the detector. Measured noise equivalent power of detector reaches
8.9×10-19 W×Hz1/2
at a wavelength of 1.55 μm
and quantum efficiency 35%.
Keywords:
superconducting single photon detectors, dark counts, noise equivalent power,
single mode fiber, background radiation.