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arXiv · 2407.20682

Nonlinear response of telecom-wavelength superconducting single-photon detectors

Patrick Mark·Sebastian Gstir·Julian Münzberg·Gregor Weihs·Robert Keil
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Abstract

We measure the nonlinearity of a telecom-wavelength superconducting nanowire single-photon detector via incoherent beam combination. At typical photon count rates and detector bias current, the observed relative deviation from a perfectly linear response is in the order of 0.1% when the flux is doubled. This arises from a balance between the counteracting nonlinearities of deadtime-induced detector saturation and of multi-photon detections. The observed behaviour is modelled empirically, which suffices for a correction of measured data. In addition, statistical simulations, taking into account the measured recovery of the detection efficiency, provide insight into possible mechanisms of multi-photon detection.

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Patrick Mark, Sebastian Gstir, Julian Münzberg, Gregor Weihs, Robert Keil. 2024-07-30. Nonlinear response of telecom-wavelength superconducting single-photon detectors. https://doi.org/10.1063/5.0231297

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