Single-photon-sensitive detector arrays are paving the way towards fast and efficient detection and certification of high-dimensional spatial entanglement. Traditionally, single-projective measurements have been used to characterize high-dimensional spatially entangled states, leading to very long measurement procedures as the number of projections required scales unfavourably with the dimension. Furthermore, to fully take advantage of the increased state space and information capacity, one must be able to deterministically probe the high-dimensional state space in parallel rather than sequentially. In recent years, single-photon-sensitive cameras have enabled this parallel detection using a variety of technologies, each with their own sets of limitations: low temporal resolution, low quantum efficiency, or higher noise levels. Consequently, the characterisation of high-dimensional entanglement using these cameras has necessitated methods such as background substraction during postprocessing, a step that opens a loophole in the certification of high-dimensional entanglement. In this work, Courme and coauthors close this loophole by employing a time-stamping single-photon-sensitive array. Unlike a camera, this array is event-driven at the single-pixel level. Owing to its high temporal resolution, low noise levels and moderate efficiency, this array enables the extraction of coincidence events from the photon arrival times, as recorded by pairs of pixels in a 6 ns coincidence window, with no background subtraction. The high data throughput of this array allows the measurement of correlations between more than 6000 modes in 400 s, quantifying entanglement in at least 14 dimensions.
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