PT Journal
AU Divochiy, A
   Marsili, F
   Bitauld, D
   Gaggero, A
   Leoni, R
   Mattioli, F
   Korneev, A
   Seleznev, V
   Kaurova, N
   Minaeva, O
   Gol'tsman, G
   Lagoudakis, KG
   Benkhaoul, M
   Lévy, F
   Fiore, A
TI Superconducting nanowire photon-number-resolving detector at telecommunication wavelengths
SO Nat. Photon.
JI Nat. Photon.
PY 2008
BP 302
EP 306
VL 2
IS 5
DI 10.1038/nphoton.2008.51
DE SSPD; photon-number-resolving
AB Optical-to-electrical conversion, which is the basis of the operation of optical detectors, can be linear or nonlinear. When high sensitivities are needed, single-photon detectors are used, which operate in a strongly nonlinear mode, their response being independent of the number of detected photons. However, photon-number-resolving detectors are needed, particularly in quantum optics, where n-photon states are routinely produced. In quantum communication and quantum information processing, the photon-number-resolving functionality is key to many protocols, such as the implementation of quantum repeaters1 and linear-optics quantum computing2. A linear detector with single-photon sensitivity can also be used for measuring a temporal waveform at extremely low light levels, such as in long-distance optical communications, fluorescence spectroscopy and optical time-domain reflectometry. We demonstrate here a photon-number-resolving detector based on parallel superconducting nanowires and capable of counting up to four photons at telecommunication wavelengths, with an ultralow dark count rate and high counting frequency.
ER