---
_id: '60136'
abstract:
- lang: eng
  text: <jats:p>Modulation conditioned on measurements on entangled photonic quantum
    states is a cornerstone technology of optical quantum information processing.
    Performing this task with low latency requires combining single-photon-level detectors
    with both electronic logic processing and optical modulation in close proximity.
    Here, we demonstrate low-latency feedforward using a quasi-photon-number-resolved
    measurement on a quantum light source. Specifically, we use a multipixel superconducting
    nanowire single-photon detector, amplifier, logic, and an integrated electro-optic
    modulator <jats:italic toggle="yes">in situ</jats:italic> below 4 K. We modulate
    the signal mode of a spontaneous parametric down-conversion source, conditional
    on a photon-number measurement of the idler mode, with a total latency of (23±3)ns.
    Furthermore, we investigate the resulting change in the photon statistics. This
    represents an important benchmark for the fastest quantum photonic feedforward
    experiments comprising measurement, amplification, logic, and modulation. This
    has direct applications in quantum computing, communication, and simulation protocols.</jats:p>
article_number: '720'
author:
- first_name: Frederik
  full_name: Thiele, Frederik
  id: '50819'
  last_name: Thiele
  orcid: 0000-0003-0663-5587
- first_name: Niklas
  full_name: Lamberty, Niklas
  id: '75307'
  last_name: Lamberty
- first_name: Thomas
  full_name: Hummel, Thomas
  id: '83846'
  last_name: Hummel
  orcid: 0000-0001-8627-2119
- first_name: Nina Amelie
  full_name: Lange, Nina Amelie
  id: '56843'
  last_name: Lange
  orcid: 0000-0001-6624-7098
- first_name: Lorenzo Manuel
  full_name: Procopio Peña, Lorenzo Manuel
  id: '105816'
  last_name: Procopio Peña
- first_name: Aishi
  full_name: Barua, Aishi
  id: '104502'
  last_name: Barua
- first_name: Sebastian
  full_name: Lengeling, Sebastian
  id: '44373'
  last_name: Lengeling
- first_name: Viktor
  full_name: Quiring, Viktor
  last_name: Quiring
- first_name: Christof
  full_name: Eigner, Christof
  id: '13244'
  last_name: Eigner
  orcid: https://orcid.org/0000-0002-5693-3083
- 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: Thiele F, Lamberty N, Hummel T, et al. Cryogenic feedforward of a photonic
    quantum state. <i>Optica</i>. 2025;12(5). doi:<a href="https://doi.org/10.1364/optica.551287">10.1364/optica.551287</a>
  apa: Thiele, F., Lamberty, N., Hummel, T., Lange, N. A., Procopio Peña, L. M., Barua,
    A., Lengeling, S., Quiring, V., Eigner, C., Silberhorn, C., &#38; Bartley, T.
    (2025). Cryogenic feedforward of a photonic quantum state. <i>Optica</i>, <i>12</i>(5),
    Article 720. <a href="https://doi.org/10.1364/optica.551287">https://doi.org/10.1364/optica.551287</a>
  bibtex: '@article{Thiele_Lamberty_Hummel_Lange_Procopio Peña_Barua_Lengeling_Quiring_Eigner_Silberhorn_et
    al._2025, title={Cryogenic feedforward of a photonic quantum state}, volume={12},
    DOI={<a href="https://doi.org/10.1364/optica.551287">10.1364/optica.551287</a>},
    number={5720}, journal={Optica}, publisher={Optica Publishing Group}, author={Thiele,
    Frederik and Lamberty, Niklas and Hummel, Thomas and Lange, Nina Amelie and Procopio
    Peña, Lorenzo Manuel and Barua, Aishi and Lengeling, Sebastian and Quiring, Viktor
    and Eigner, Christof and Silberhorn, Christine and et al.}, year={2025} }'
  chicago: Thiele, Frederik, Niklas Lamberty, Thomas Hummel, Nina Amelie Lange, Lorenzo
    Manuel Procopio Peña, Aishi Barua, Sebastian Lengeling, et al. “Cryogenic Feedforward
    of a Photonic Quantum State.” <i>Optica</i> 12, no. 5 (2025). <a href="https://doi.org/10.1364/optica.551287">https://doi.org/10.1364/optica.551287</a>.
  ieee: 'F. Thiele <i>et al.</i>, “Cryogenic feedforward of a photonic quantum state,”
    <i>Optica</i>, vol. 12, no. 5, Art. no. 720, 2025, doi: <a href="https://doi.org/10.1364/optica.551287">10.1364/optica.551287</a>.'
  mla: Thiele, Frederik, et al. “Cryogenic Feedforward of a Photonic Quantum State.”
    <i>Optica</i>, vol. 12, no. 5, 720, Optica Publishing Group, 2025, doi:<a href="https://doi.org/10.1364/optica.551287">10.1364/optica.551287</a>.
  short: F. Thiele, N. Lamberty, T. Hummel, N.A. Lange, L.M. Procopio Peña, A. Barua,
    S. Lengeling, V. Quiring, C. Eigner, C. Silberhorn, T. Bartley, Optica 12 (2025).
date_created: 2025-06-04T18:34:16Z
date_updated: 2025-06-12T09:56:47Z
doi: 10.1364/optica.551287
intvolume: '        12'
issue: '5'
language:
- iso: eng
publication: Optica
publication_identifier:
  issn:
  - 2334-2536
publication_status: published
publisher: Optica Publishing Group
status: public
title: Cryogenic feedforward of a photonic quantum state
type: journal_article
user_id: '56843'
volume: 12
year: '2025'
...