[{"publication":"Optica Quantum","type":"journal_article","status":"public","abstract":[{"text":"<jats:p>Superconducting nanowire single-photon detectors (SNSPDs) have been widely used to study the discrete nature of quantum states of light in the form of photon-counting experiments. We show that SNSPDs can also be used to study continuous variables of optical quantum states by performing homodyne detection at a bandwidth of 400 kHz. By measuring the interference of a continuous-wave field of a local oscillator with the field of the vacuum state using two SNSPDs, we show that the variance of the difference in count rates is linearly proportional to the photon flux of the local oscillator over almost five orders of magnitude. The resulting shot-noise clearance of (46.0 ± 1.1) dB is the highest reported clearance for a balanced optical homodyne detector, demonstrating their potential for measuring highly squeezed states in the continuous-wave regime. In addition, we measured a CMRR = 22.4 dB. From the joint click counting statistics, we also measure the phase-dependent quadrature of a weak coherent state to demonstrate our device’s functionality as a homodyne detector.</jats:p>","lang":"eng"}],"department":[{"_id":"15"},{"_id":"623"}],"user_id":"55629","_id":"50840","project":[{"_id":"191","name":"PhoQuant: Photonische Quantencomputer -  Quantencomputing Testplattform"},{"_id":"239","name":"ERC-Grant: QuESADILLA: Quantum Engineering Superconducting Array Detectors in Low-Light Applications"},{"_id":"209","name":"ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender Elektronik"}],"language":[{"iso":"eng"}],"article_number":"1","issue":"1","publication_identifier":{"issn":["2837-6714"]},"publication_status":"published","intvolume":"         2","citation":{"ieee":"M. Protte, T. Schapeler, J. Sperling, and T. Bartley, “Low-noise balanced homodyne detection with superconducting nanowire single-photon detectors,” <i>Optica Quantum</i>, vol. 2, no. 1, Art. no. 1, 2024, doi: <a href=\"https://doi.org/10.1364/opticaq.502201\">10.1364/opticaq.502201</a>.","chicago":"Protte, Maximilian, Timon Schapeler, Jan Sperling, and Tim Bartley. “Low-Noise Balanced Homodyne Detection with Superconducting Nanowire Single-Photon Detectors.” <i>Optica Quantum</i> 2, no. 1 (2024). <a href=\"https://doi.org/10.1364/opticaq.502201\">https://doi.org/10.1364/opticaq.502201</a>.","ama":"Protte M, Schapeler T, Sperling J, Bartley T. Low-noise balanced homodyne detection with superconducting nanowire single-photon detectors. <i>Optica Quantum</i>. 2024;2(1). doi:<a href=\"https://doi.org/10.1364/opticaq.502201\">10.1364/opticaq.502201</a>","apa":"Protte, M., Schapeler, T., Sperling, J., &#38; Bartley, T. (2024). Low-noise balanced homodyne detection with superconducting nanowire single-photon detectors. <i>Optica Quantum</i>, <i>2</i>(1), Article 1. <a href=\"https://doi.org/10.1364/opticaq.502201\">https://doi.org/10.1364/opticaq.502201</a>","mla":"Protte, Maximilian, et al. “Low-Noise Balanced Homodyne Detection with Superconducting Nanowire Single-Photon Detectors.” <i>Optica Quantum</i>, vol. 2, no. 1, 1, Optica Publishing Group, 2024, doi:<a href=\"https://doi.org/10.1364/opticaq.502201\">10.1364/opticaq.502201</a>.","short":"M. Protte, T. Schapeler, J. Sperling, T. Bartley, Optica Quantum 2 (2024).","bibtex":"@article{Protte_Schapeler_Sperling_Bartley_2024, title={Low-noise balanced homodyne detection with superconducting nanowire single-photon detectors}, volume={2}, DOI={<a href=\"https://doi.org/10.1364/opticaq.502201\">10.1364/opticaq.502201</a>}, number={11}, journal={Optica Quantum}, publisher={Optica Publishing Group}, author={Protte, Maximilian and Schapeler, Timon and Sperling, Jan and Bartley, Tim}, year={2024} }"},"year":"2024","volume":2,"date_created":"2024-01-25T11:48:02Z","author":[{"first_name":"Maximilian","last_name":"Protte","id":"46170","full_name":"Protte, Maximilian"},{"first_name":"Timon","full_name":"Schapeler, Timon","id":"55629","orcid":"0000-0001-7652-1716","last_name":"Schapeler"},{"full_name":"Sperling, Jan","id":"75127","last_name":"Sperling","orcid":"0000-0002-5844-3205","first_name":"Jan"},{"first_name":"Tim","id":"49683","full_name":"Bartley, Tim","last_name":"Bartley"}],"oa":"1","date_updated":"2025-12-18T17:06:27Z","publisher":"Optica Publishing Group","doi":"10.1364/opticaq.502201","main_file_link":[{"open_access":"1"}],"title":"Low-noise balanced homodyne detection with superconducting nanowire single-photon detectors"},{"publication":"Physical Review A","type":"journal_article","status":"public","_id":"33670","project":[{"_id":"209","name":"ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender Elektronik"}],"department":[{"_id":"15"},{"_id":"230"},{"_id":"623"}],"user_id":"55629","article_number":"013701","language":[{"iso":"eng"}],"publication_identifier":{"issn":["2469-9926","2469-9934"]},"publication_status":"published","issue":"1","year":"2022","intvolume":"       106","citation":{"apa":"Schapeler, T., &#38; Bartley, T. (2022). Information extraction in photon-counting experiments. <i>Physical Review A</i>, <i>106</i>(1), Article 013701. <a href=\"https://doi.org/10.1103/physreva.106.013701\">https://doi.org/10.1103/physreva.106.013701</a>","short":"T. Schapeler, T. Bartley, Physical Review A 106 (2022).","bibtex":"@article{Schapeler_Bartley_2022, title={Information extraction in photon-counting experiments}, volume={106}, DOI={<a href=\"https://doi.org/10.1103/physreva.106.013701\">10.1103/physreva.106.013701</a>}, number={1013701}, journal={Physical Review A}, publisher={American Physical Society (APS)}, author={Schapeler, Timon and Bartley, Tim}, year={2022} }","mla":"Schapeler, Timon, and Tim Bartley. “Information Extraction in Photon-Counting Experiments.” <i>Physical Review A</i>, vol. 106, no. 1, 013701, American Physical Society (APS), 2022, doi:<a href=\"https://doi.org/10.1103/physreva.106.013701\">10.1103/physreva.106.013701</a>.","chicago":"Schapeler, Timon, and Tim Bartley. “Information Extraction in Photon-Counting Experiments.” <i>Physical Review A</i> 106, no. 1 (2022). <a href=\"https://doi.org/10.1103/physreva.106.013701\">https://doi.org/10.1103/physreva.106.013701</a>.","ieee":"T. Schapeler and T. Bartley, “Information extraction in photon-counting experiments,” <i>Physical Review A</i>, vol. 106, no. 1, Art. no. 013701, 2022, doi: <a href=\"https://doi.org/10.1103/physreva.106.013701\">10.1103/physreva.106.013701</a>.","ama":"Schapeler T, Bartley T. Information extraction in photon-counting experiments. <i>Physical Review A</i>. 2022;106(1). doi:<a href=\"https://doi.org/10.1103/physreva.106.013701\">10.1103/physreva.106.013701</a>"},"publisher":"American Physical Society (APS)","date_updated":"2025-12-18T17:07:12Z","volume":106,"author":[{"first_name":"Timon","id":"55629","full_name":"Schapeler, Timon","last_name":"Schapeler","orcid":"0000-0001-7652-1716"},{"first_name":"Tim","last_name":"Bartley","id":"49683","full_name":"Bartley, Tim"}],"date_created":"2022-10-11T07:13:12Z","title":"Information extraction in photon-counting experiments","doi":"10.1103/physreva.106.013701"},{"_id":"23727","project":[{"_id":"209","name":"ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender Elektronik"}],"department":[{"_id":"15"},{"_id":"230"}],"user_id":"55629","article_number":"064002","language":[{"iso":"eng"}],"publication":"Superconductor Science and Technology","type":"journal_article","status":"public","date_updated":"2025-12-18T17:07:44Z","author":[{"id":"55629","full_name":"Schapeler, Timon","last_name":"Schapeler","orcid":"0000-0001-7652-1716","first_name":"Timon"},{"full_name":"Höpker, Jan Philipp","id":"33913","last_name":"Höpker","first_name":"Jan Philipp"},{"id":"49683","full_name":"Bartley, Tim","last_name":"Bartley","first_name":"Tim"}],"date_created":"2021-09-03T08:03:34Z","title":"Quantum detector tomography of a high dynamic-range superconducting nanowire single-photon detector","doi":"10.1088/1361-6668/abee9a","publication_identifier":{"issn":["0953-2048","1361-6668"]},"publication_status":"published","year":"2021","citation":{"ama":"Schapeler T, Höpker JP, Bartley T. Quantum detector tomography of a high dynamic-range superconducting nanowire single-photon detector. <i>Superconductor Science and Technology</i>. Published online 2021. doi:<a href=\"https://doi.org/10.1088/1361-6668/abee9a\">10.1088/1361-6668/abee9a</a>","chicago":"Schapeler, Timon, Jan Philipp Höpker, and Tim Bartley. “Quantum Detector Tomography of a High Dynamic-Range Superconducting Nanowire Single-Photon Detector.” <i>Superconductor Science and Technology</i>, 2021. <a href=\"https://doi.org/10.1088/1361-6668/abee9a\">https://doi.org/10.1088/1361-6668/abee9a</a>.","ieee":"T. Schapeler, J. P. Höpker, and T. Bartley, “Quantum detector tomography of a high dynamic-range superconducting nanowire single-photon detector,” <i>Superconductor Science and Technology</i>, Art. no. 064002, 2021, doi: <a href=\"https://doi.org/10.1088/1361-6668/abee9a\">10.1088/1361-6668/abee9a</a>.","apa":"Schapeler, T., Höpker, J. P., &#38; Bartley, T. (2021). Quantum detector tomography of a high dynamic-range superconducting nanowire single-photon detector. <i>Superconductor Science and Technology</i>, Article 064002. <a href=\"https://doi.org/10.1088/1361-6668/abee9a\">https://doi.org/10.1088/1361-6668/abee9a</a>","bibtex":"@article{Schapeler_Höpker_Bartley_2021, title={Quantum detector tomography of a high dynamic-range superconducting nanowire single-photon detector}, DOI={<a href=\"https://doi.org/10.1088/1361-6668/abee9a\">10.1088/1361-6668/abee9a</a>}, number={064002}, journal={Superconductor Science and Technology}, author={Schapeler, Timon and Höpker, Jan Philipp and Bartley, Tim}, year={2021} }","short":"T. Schapeler, J.P. Höpker, T. Bartley, Superconductor Science and Technology (2021).","mla":"Schapeler, Timon, et al. “Quantum Detector Tomography of a High Dynamic-Range Superconducting Nanowire Single-Photon Detector.” <i>Superconductor Science and Technology</i>, 064002, 2021, doi:<a href=\"https://doi.org/10.1088/1361-6668/abee9a\">10.1088/1361-6668/abee9a</a>."}},{"issue":"4","year":"2020","date_created":"2023-01-22T17:13:35Z","publisher":"Optica Publishing Group","title":"Single-channel electronic readout of a multipixel superconducting nanowire single photon detector","publication":"Optics Express","abstract":[{"text":"<jats:p>We present a time-over-threshold readout technique to count the number of activated pixels from an array of superconducting nanowire single photon detectors (SNSPDs). This technique places no additional heatload on the cryostat, and retains the intrinsic count rate of the time-tagger. We demonstrate proof-of-principle operation with respect to a four-pixel device. Furthermore, we show that, given some permissible error threshold, the number of pixels that can be reliably read out scales linearly with the intrinsic signal-to-noise ratio of the individual pixel response.</jats:p>","lang":"eng"}],"language":[{"iso":"eng"}],"keyword":["Atomic and Molecular Physics","and Optics"],"publication_status":"published","publication_identifier":{"issn":["1094-4087"]},"citation":{"ieee":"J. Tiedau, T. Schapeler, V. Anant, H. Fedder, C. Silberhorn, and T. Bartley, “Single-channel electronic readout of a multipixel superconducting nanowire single photon detector,” <i>Optics Express</i>, vol. 28, no. 4, Art. no. 5528, 2020, doi: <a href=\"https://doi.org/10.1364/oe.383111\">10.1364/oe.383111</a>.","chicago":"Tiedau, Johannes, Timon Schapeler, Vikas Anant, Helmut Fedder, Christine Silberhorn, and Tim Bartley. “Single-Channel Electronic Readout of a Multipixel Superconducting Nanowire Single Photon Detector.” <i>Optics Express</i> 28, no. 4 (2020). <a href=\"https://doi.org/10.1364/oe.383111\">https://doi.org/10.1364/oe.383111</a>.","ama":"Tiedau J, Schapeler T, Anant V, Fedder H, Silberhorn C, Bartley T. Single-channel electronic readout of a multipixel superconducting nanowire single photon detector. <i>Optics Express</i>. 2020;28(4). doi:<a href=\"https://doi.org/10.1364/oe.383111\">10.1364/oe.383111</a>","mla":"Tiedau, Johannes, et al. “Single-Channel Electronic Readout of a Multipixel Superconducting Nanowire Single Photon Detector.” <i>Optics Express</i>, vol. 28, no. 4, 5528, Optica Publishing Group, 2020, doi:<a href=\"https://doi.org/10.1364/oe.383111\">10.1364/oe.383111</a>.","short":"J. Tiedau, T. Schapeler, V. Anant, H. Fedder, C. Silberhorn, T. Bartley, Optics Express 28 (2020).","bibtex":"@article{Tiedau_Schapeler_Anant_Fedder_Silberhorn_Bartley_2020, title={Single-channel electronic readout of a multipixel superconducting nanowire single photon detector}, volume={28}, DOI={<a href=\"https://doi.org/10.1364/oe.383111\">10.1364/oe.383111</a>}, number={45528}, journal={Optics Express}, publisher={Optica Publishing Group}, author={Tiedau, Johannes and Schapeler, Timon and Anant, Vikas and Fedder, Helmut and Silberhorn, Christine and Bartley, Tim}, year={2020} }","apa":"Tiedau, J., Schapeler, T., Anant, V., Fedder, H., Silberhorn, C., &#38; Bartley, T. (2020). Single-channel electronic readout of a multipixel superconducting nanowire single photon detector. <i>Optics Express</i>, <i>28</i>(4), Article 5528. <a href=\"https://doi.org/10.1364/oe.383111\">https://doi.org/10.1364/oe.383111</a>"},"intvolume":"        28","author":[{"full_name":"Tiedau, Johannes","last_name":"Tiedau","first_name":"Johannes"},{"last_name":"Schapeler","orcid":"0000-0001-7652-1716","id":"55629","full_name":"Schapeler, Timon","first_name":"Timon"},{"first_name":"Vikas","full_name":"Anant, Vikas","last_name":"Anant"},{"first_name":"Helmut","full_name":"Fedder, Helmut","last_name":"Fedder"},{"id":"26263","full_name":"Silberhorn, Christine","last_name":"Silberhorn","first_name":"Christine"},{"first_name":"Tim","last_name":"Bartley","full_name":"Bartley, Tim","id":"49683"}],"volume":28,"date_updated":"2025-12-18T17:10:24Z","doi":"10.1364/oe.383111","type":"journal_article","status":"public","user_id":"55629","department":[{"_id":"288"},{"_id":"15"},{"_id":"623"},{"_id":"230"}],"project":[{"_id":"237","name":"PhoG: Sub-Poissonian Photon Gun by Coherent Diffusive Photonics - EU Flagship Project"},{"name":"ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender Elektronik","_id":"209"}],"_id":"37933","article_number":"5528"},{"publication":"Optics Express","type":"journal_article","status":"public","department":[{"_id":"15"},{"_id":"230"}],"user_id":"55629","_id":"20156","project":[{"name":"ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender Elektronik","_id":"209"}],"language":[{"iso":"eng"}],"article_number":"33035","publication_identifier":{"issn":["1094-4087"]},"publication_status":"published","citation":{"apa":"Schapeler, T., Höpker, J. P., &#38; Bartley, T. (2020). Quantum detector tomography of a 2×2 multi-pixel array of superconducting nanowire single photon detectors. <i>Optics Express</i>, Article 33035. <a href=\"https://doi.org/10.1364/oe.404285\">https://doi.org/10.1364/oe.404285</a>","bibtex":"@article{Schapeler_Höpker_Bartley_2020, title={Quantum detector tomography of a 2×2 multi-pixel array of superconducting nanowire single photon detectors}, DOI={<a href=\"https://doi.org/10.1364/oe.404285\">10.1364/oe.404285</a>}, number={33035}, journal={Optics Express}, author={Schapeler, Timon and Höpker, Jan Philipp and Bartley, Tim}, year={2020} }","mla":"Schapeler, Timon, et al. “Quantum Detector Tomography of a 2×2 Multi-Pixel Array of Superconducting Nanowire Single Photon Detectors.” <i>Optics Express</i>, 33035, 2020, doi:<a href=\"https://doi.org/10.1364/oe.404285\">10.1364/oe.404285</a>.","short":"T. Schapeler, J.P. Höpker, T. Bartley, Optics Express (2020).","ama":"Schapeler T, Höpker JP, Bartley T. Quantum detector tomography of a 2×2 multi-pixel array of superconducting nanowire single photon detectors. <i>Optics Express</i>. Published online 2020. doi:<a href=\"https://doi.org/10.1364/oe.404285\">10.1364/oe.404285</a>","chicago":"Schapeler, Timon, Jan Philipp Höpker, and Tim Bartley. “Quantum Detector Tomography of a 2×2 Multi-Pixel Array of Superconducting Nanowire Single Photon Detectors.” <i>Optics Express</i>, 2020. <a href=\"https://doi.org/10.1364/oe.404285\">https://doi.org/10.1364/oe.404285</a>.","ieee":"T. Schapeler, J. P. Höpker, and T. Bartley, “Quantum detector tomography of a 2×2 multi-pixel array of superconducting nanowire single photon detectors,” <i>Optics Express</i>, Art. no. 33035, 2020, doi: <a href=\"https://doi.org/10.1364/oe.404285\">10.1364/oe.404285</a>."},"year":"2020","author":[{"last_name":"Schapeler","orcid":"0000-0001-7652-1716","full_name":"Schapeler, Timon","id":"55629","first_name":"Timon"},{"full_name":"Höpker, Jan Philipp","id":"33913","last_name":"Höpker","first_name":"Jan Philipp"},{"first_name":"Tim","last_name":"Bartley","full_name":"Bartley, Tim","id":"49683"}],"date_created":"2020-10-21T11:02:41Z","date_updated":"2025-12-18T17:08:01Z","doi":"10.1364/oe.404285","title":"Quantum detector tomography of a 2×2 multi-pixel array of superconducting nanowire single photon detectors"}]