Photon-number resolving detector based on a series array of superconducting nanowires
S. Jahanmirinejad, G. Frucci, F. Mattioli, Dondu Sahin, Alessandro Gaggero, Roberto Leoni, Andrea Fiore · Applied Physics Letters · 2012
We present the experimental demonstration of a superconducting photon number resolving detector. It is based on the series connection of N superconducting nanowires, each connected in parallel to an integrated resistor. The device provides a single voltage readout, proportional to the number of photons detected in distinct nanowires. Clearly separated output levels corresponding to the detection of n¼14 photons are observed in a 4-element detector fabricated from an NbN film on GaAs substrate, with a single-photon system quantum efficiency of 2.6% at k¼1.3 lm. The series-nanowire structure is promising in view of its scalability to large photon numbers and high efficiencies.