---
_id: '50840'
abstract:
- lang: eng
  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>
article_number: '1'
author:
- first_name: Maximilian
  full_name: Protte, Maximilian
  id: '46170'
  last_name: Protte
- first_name: Timon
  full_name: Schapeler, Timon
  id: '55629'
  last_name: Schapeler
  orcid: 0000-0001-7652-1716
- first_name: Jan
  full_name: Sperling, Jan
  id: '75127'
  last_name: Sperling
  orcid: 0000-0002-5844-3205
- first_name: Tim
  full_name: Bartley, Tim
  id: '49683'
  last_name: Bartley
citation:
  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>
  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}
    }'
  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>.
  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>.'
  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).
date_created: 2024-01-25T11:48:02Z
date_updated: 2025-12-18T17:06:27Z
department:
- _id: '15'
- _id: '623'
doi: 10.1364/opticaq.502201
intvolume: '         2'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
oa: '1'
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'
publication: Optica Quantum
publication_identifier:
  issn:
  - 2837-6714
publication_status: published
publisher: Optica Publishing Group
status: public
title: Low-noise balanced homodyne detection with superconducting nanowire single-photon
  detectors
type: journal_article
user_id: '55629'
volume: 2
year: '2024'
...
---
_id: '33670'
article_number: '013701'
author:
- first_name: Timon
  full_name: Schapeler, Timon
  id: '55629'
  last_name: Schapeler
  orcid: 0000-0001-7652-1716
- first_name: Tim
  full_name: Bartley, Tim
  id: '49683'
  last_name: Bartley
citation:
  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>
  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>
  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} }'
  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>.'
  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>.
  short: T. Schapeler, T. Bartley, Physical Review A 106 (2022).
date_created: 2022-10-11T07:13:12Z
date_updated: 2025-12-18T17:07:12Z
department:
- _id: '15'
- _id: '230'
- _id: '623'
doi: 10.1103/physreva.106.013701
intvolume: '       106'
issue: '1'
language:
- iso: eng
project:
- _id: '209'
  name: 'ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender
    Elektronik'
publication: Physical Review A
publication_identifier:
  issn:
  - 2469-9926
  - 2469-9934
publication_status: published
publisher: American Physical Society (APS)
status: public
title: Information extraction in photon-counting experiments
type: journal_article
user_id: '55629'
volume: 106
year: '2022'
...
---
_id: '23727'
article_number: '064002'
author:
- first_name: Timon
  full_name: Schapeler, Timon
  id: '55629'
  last_name: Schapeler
  orcid: 0000-0001-7652-1716
- first_name: Jan Philipp
  full_name: Höpker, Jan Philipp
  id: '33913'
  last_name: Höpker
- first_name: Tim
  full_name: Bartley, Tim
  id: '49683'
  last_name: Bartley
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>
  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} }'
  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>.'
  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>.
  short: T. Schapeler, J.P. Höpker, T. Bartley, Superconductor Science and Technology
    (2021).
date_created: 2021-09-03T08:03:34Z
date_updated: 2025-12-18T17:07:44Z
department:
- _id: '15'
- _id: '230'
doi: 10.1088/1361-6668/abee9a
language:
- iso: eng
project:
- _id: '209'
  name: 'ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender
    Elektronik'
publication: Superconductor Science and Technology
publication_identifier:
  issn:
  - 0953-2048
  - 1361-6668
publication_status: published
status: public
title: Quantum detector tomography of a high dynamic-range superconducting nanowire
  single-photon detector
type: journal_article
user_id: '55629'
year: '2021'
...
---
_id: '37933'
abstract:
- lang: eng
  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>
article_number: '5528'
author:
- first_name: Johannes
  full_name: Tiedau, Johannes
  last_name: Tiedau
- first_name: Timon
  full_name: Schapeler, Timon
  id: '55629'
  last_name: Schapeler
  orcid: 0000-0001-7652-1716
- first_name: Vikas
  full_name: Anant, Vikas
  last_name: Anant
- first_name: Helmut
  full_name: Fedder, Helmut
  last_name: Fedder
- first_name: Christine
  full_name: Silberhorn, Christine
  id: '26263'
  last_name: Silberhorn
- first_name: Tim
  full_name: Bartley, Tim
  id: '49683'
  last_name: Bartley
citation:
  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>
  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>
  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} }'
  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>.
  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>.'
  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).
date_created: 2023-01-22T17:13:35Z
date_updated: 2025-12-18T17:10:24Z
department:
- _id: '288'
- _id: '15'
- _id: '623'
- _id: '230'
doi: 10.1364/oe.383111
intvolume: '        28'
issue: '4'
keyword:
- Atomic and Molecular Physics
- and Optics
language:
- iso: eng
project:
- _id: '237'
  name: 'PhoG: Sub-Poissonian Photon Gun by Coherent Diffusive Photonics - EU Flagship
    Project'
- _id: '209'
  name: 'ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender
    Elektronik'
publication: Optics Express
publication_identifier:
  issn:
  - 1094-4087
publication_status: published
publisher: Optica Publishing Group
status: public
title: Single-channel electronic readout of a multipixel superconducting nanowire
  single photon detector
type: journal_article
user_id: '55629'
volume: 28
year: '2020'
...
---
_id: '20156'
article_number: '33035'
author:
- first_name: Timon
  full_name: Schapeler, Timon
  id: '55629'
  last_name: Schapeler
  orcid: 0000-0001-7652-1716
- first_name: Jan Philipp
  full_name: Höpker, Jan Philipp
  id: '33913'
  last_name: Höpker
- first_name: Tim
  full_name: Bartley, Tim
  id: '49683'
  last_name: Bartley
citation:
  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>
  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} }'
  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>.'
  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).
date_created: 2020-10-21T11:02:41Z
date_updated: 2025-12-18T17:08:01Z
department:
- _id: '15'
- _id: '230'
doi: 10.1364/oe.404285
language:
- iso: eng
project:
- _id: '209'
  name: 'ISOQC: Quantenkommunikation mit integrierter Optik im Zusammenhang mit supraleitender
    Elektronik'
publication: Optics Express
publication_identifier:
  issn:
  - 1094-4087
publication_status: published
status: public
title: Quantum detector tomography of a 2×2 multi-pixel array of superconducting nanowire
  single photon detectors
type: journal_article
user_id: '55629'
year: '2020'
...