Nanowire superconducting single-photon detectors on GaAs for integrated quantum photonic applications

We demonstrate efficient nanowire superconducting single photon detectors SSPDs based on NbN thin films grown on GaAs. NbN films ranging from 3 to 5 nm in thickness have been deposited by dc magnetron sputtering on GaAs substrates at 350 °C. These films show superconducting properties comparable to similar films grown on sapphire and MgO. In order to demonstrate the potential for monolithic integration, SSPDs were fabricated and measured on GaAs/AlAs Bragg mirrors, showing a clear cavity enhancement, with a peak quantum efficiency of 18.3% at =1300 nm and T=4.2 K.