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arXiv · 1706.00949

Beyond conventional photon-number detection with click detectors

Johannes Kröger·Thomas Ahrens·Jan Sperling·Werner Vogel·Heinrich Stolz·Boris Hage
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Abstract

Photon-number measurements are a fundamental technique for the discrimination and characterization of quantum states of light. Beyond the abilities of state-of-the-art devices, we present measurements with an array of 100 avalanche photodiodes exposed to photon-numbers ranging from well below to significantly above one photon per diode. Despite each single diode only discriminating between zero and non-zero photon-numbers we are able to extract characteristic information about the quantum state. We demonstrate a vast enhancement of the applicable intensity range by two orders of magnitude relative to the standard application of such devices. It turns out that the probabilistic mapping of arbitrary photon-numbers on a finite number of registered clicks is not per se a disadvantage compared with true photon counters. Such detector arrays can bridge the gap between single-photon and linear detection, by directly using the recorded data, without the need of elaborate data reconstruction methods.

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Johannes Kröger, Thomas Ahrens, Jan Sperling, Werner Vogel, Heinrich Stolz, Boris Hage. 2017-06-03. Beyond conventional photon-number detection with click detectors. https://arxiv.org/abs/1706.00949

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