RESUMEN
We present a 1024-element near-infrared imaging array of superconducting nanowire single photon detectors (SNSPDs) using a 32×32 row-column multiplexing architecture. The array has an active area of 0.96 × 0.96 mm, making it the largest SNSPD array reported to date in terms of both active area and pixel count. Using a 64-channel time-tagging readout, we have characterized the array's yield, efficiency, and timing resolution. Large arrays of SNSPDs are desirable for applications such as imaging, spectroscopy, or particle detection.
RESUMEN
We present a loophole-free violation of local realism using entangled photon pairs. We ensure that all relevant events in our Bell test are spacelike separated by placing the parties far enough apart and by using fast random number generators and high-speed polarization measurements. A high-quality polarization-entangled source of photons, combined with high-efficiency, low-noise, single-photon detectors, allows us to make measurements without requiring any fair-sampling assumptions. Using a hypothesis test, we compute p values as small as 5.9×10^{-9} for our Bell violation while maintaining the spacelike separation of our events. We estimate the degree to which a local realistic system could predict our measurement choices. Accounting for this predictability, our smallest adjusted p value is 2.3×10^{-7}. We therefore reject the hypothesis that local realism governs our experiment.