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arXiv · 2109.08347

Experimental observation of anomalous supralinear response of single-photon detectors

Josef Hloušek·Ivo Straka·Miroslav Ježek
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Abstract

We demonstrate a direct single-source measurement of absolute nonlinearity of single-photon detectors with unprecedented accuracy. We discover a surprising supralinear behavior of single-photon avalanche diodes and show that it cannot be explained using known theoretical models. We also fully characterize sub- and supra-linear operation regimes of superconducting nanowire single-photon detectors and uncover the supralinearity under faint continuous illumination. The results identify new detector anomalies that supersede existing knowledge of nonlinear effects at the single-photon level.

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Josef Hloušek, Ivo Straka, Miroslav Ježek. 2021-09-17. Experimental observation of anomalous supralinear response of single-photon detectors. https://doi.org/10.1063/5.0106987

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