Waveguide integrated low noise NbTiN nanowire single-photon detectors with milli-Hz dark count rate.

Department of Electrical Engineering, Yale University, New Haven, Connecticut, 06511, United States.
Scientific Reports (Impact Factor: 5.08). 05/2013; 3:1893. DOI: 10.1038/srep01893
Source: PubMed

ABSTRACT Superconducting nanowire single-photon detectors are an ideal match for integrated quantum photonic circuits due to their high detection efficiency for telecom wavelength photons. Quantum optical technology also requires single-photon detection with low dark count rate and high timing accuracy. Here we present very low noise superconducting nanowire single-photon detectors based on NbTiN thin films patterned directly on top of Si3N4 waveguides. We systematically investigate a large variety of detector designs and characterize their detection noise performance. Milli-Hz dark count rates are demonstrated over the entire operating range of the nanowire detectors which also feature low timing jitter. The ultra-low dark count rate, in combination with the high detection efficiency inherent to our travelling wave detector geometry, gives rise to a measured noise equivalent power at the 10(-20) W/Hz(1/2) level.

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