article published Timon Schapeler author 556290000-0001-7652-1716 Isabell Mischke author Fabian Schlue author 63579 Michael Stefszky author 42777 Benjamin Brecht author 271500000-0003-4140-0556 Christine Silberhorn author 26263 Tim Bartley author 49683 15 department 623 department 288 department PhoQuant: Photonische Quantencomputer - Quantencomputing Testplattform project ERC-Grant: QuESADILLA: Quantum Engineering Superconducting Array Detectors in Low-Light Applications project <jats:p>Superconducting nanowire single-photon detectors (SNSPDs) can enable photon-number resolution (PNR) based on accurate measurements of the detector’s response time to few-photon optical pulses. In this work, we investigate the impact of the optical pulse shape and duration on the accuracy of this method. We find that Gaussian temporal pulse shapes yield cleaner arrival-time histograms and, thus, more accurate PNR, compared to bandpass-filtered pulses of equal bandwidth. For low system jitter and an optical pulse duration comparable to the other jitter contributions, photon numbers can be discriminated in our system with a commercial SNSPD. At 60 ps optical pulse duration, photon-number discrimination is significantly reduced. Furthermore, we highlight the importance of using the correct arrival-time histogram model when analyzing photon-number assignment. Using exponentially modified Gaussian distributions, instead of the commonly used Gaussian distributions, we can more accurately determine photon-number misidentification probabilities. Finally, we reconstruct the positive operator-valued measures of the detector, revealing sharp features that indicate the intrinsic PNR capabilities.</jats:p> AIP Publishing2026 eng 2835-010310.1063/5.0304127 31 Schapeler, T., Mischke, I., Schlue, F., Stefszky, M., Brecht, B., Silberhorn, C., &#38; Bartley, T. (2026). Practical considerations for assignment of photon numbers with SNSPDs. <i>APL Quantum</i>, <i>3</i>(1), Article 016102. <a href="https://doi.org/10.1063/5.0304127">https://doi.org/10.1063/5.0304127</a> @article{Schapeler_Mischke_Schlue_Stefszky_Brecht_Silberhorn_Bartley_2026, title={Practical considerations for assignment of photon numbers with SNSPDs}, volume={3}, DOI={<a href="https://doi.org/10.1063/5.0304127">10.1063/5.0304127</a>}, number={1016102}, journal={APL Quantum}, publisher={AIP Publishing}, author={Schapeler, Timon and Mischke, Isabell and Schlue, Fabian and Stefszky, Michael and Brecht, Benjamin and Silberhorn, Christine and Bartley, Tim}, year={2026} } Schapeler, Timon, et al. “Practical Considerations for Assignment of Photon Numbers with SNSPDs.” <i>APL Quantum</i>, vol. 3, no. 1, 016102, AIP Publishing, 2026, doi:<a href="https://doi.org/10.1063/5.0304127">10.1063/5.0304127</a>. T. Schapeler, I. Mischke, F. Schlue, M. Stefszky, B. Brecht, C. Silberhorn, T. Bartley, APL Quantum 3 (2026). T. Schapeler <i>et al.</i>, “Practical considerations for assignment of photon numbers with SNSPDs,” <i>APL Quantum</i>, vol. 3, no. 1, Art. no. 016102, 2026, doi: <a href="https://doi.org/10.1063/5.0304127">10.1063/5.0304127</a>. Schapeler, Timon, Isabell Mischke, Fabian Schlue, Michael Stefszky, Benjamin Brecht, Christine Silberhorn, and Tim Bartley. “Practical Considerations for Assignment of Photon Numbers with SNSPDs.” <i>APL Quantum</i> 3, no. 1 (2026). <a href="https://doi.org/10.1063/5.0304127">https://doi.org/10.1063/5.0304127</a>. Schapeler T, Mischke I, Schlue F, et al. Practical considerations for assignment of photon numbers with SNSPDs. <i>APL Quantum</i>. 2026;3(1). doi:<a href="https://doi.org/10.1063/5.0304127">10.1063/5.0304127</a> 634512026-01-05T10:00:58Z2026-03-25T08:00:27Z