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arXiv · 2504.01185

Characterizing and exploiting cross-talk effect in SPAD arrays for two-photon interference

Sergei Kulkov·Lada Radmacherova·Ondrej Matousek·Lou-Ann Pestana De Sousa·Ermanno Bernasconi·Claudio Bruschini·Tommaso Milanese·Edoardo Charbon·Andrei Nomerotski·Peter Svihra
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Abstract

SPAD arrays are becoming a popular choice for measuring two-photon interference effects thanks to their high timing precision, fast readout, and high quantum efficiency. However, such sensors are affected by cross-talk that may mimic the useful signal. Even with a low probability of seeing cross-talk effect between neighboring SPADs, it was found that it still may reach the farther channels up to a half of millimeter away. Moreover, the use of microlenses that help SPADs achieve even better efficiency further boosts the cross-talk effect. In this work, we characterize the cross-talk effect and compare it to the Hanbury Brown-Twiss effect in the LinoSPAD2 camera, which has a linear sensor of 512 SPADs. Additionally, we compare the results between sensors with and without the microlenses. Finally, we present a timing calibration technique for the detector that utilizes the cross-talk effect.

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Sergei Kulkov, Lada Radmacherova, Ondrej Matousek, Lou-Ann Pestana De Sousa, Ermanno Bernasconi, Claudio Bruschini, Tommaso Milanese, Edoardo Charbon, Andrei Nomerotski, Peter Svihra. 2025-04-01. Characterizing and exploiting cross-talk effect in SPAD arrays for two-photon interference. https://arxiv.org/abs/2504.01185

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