---
OA_place: repository
OA_type: green
_id: '21870'
abstract:
- lang: eng
  text: Superconducting qubits are a leading candidate for utility-scale quantum computing
    due to their fast gate speeds and steadily decreasing error rates. The requirement
    for millikelvin operating temperatures, however, creates a significant scaling
    bottleneck. Modular architectures using optical fiber links could bridge separate
    cryogenic nodes, but superconducting circuits do not have coherent optical transitions
    and microwave-to-optical conversion has not been shown for any non-classical photon
    state. In this work, we demonstrate the on-demand generation and tomographic reconstruction
    of itinerant single microwave photons at 8.9 GHz from a superconducting qubit.
    We upconvert this non-Gaussian state with a transducer added noise below 0.012
    quanta and count the converted telecom photons at 193.4 THz with a signal-to-noise
    ratio of up to 5.1$\pm$1.1. We characterize the trade-offs between throughput
    and noise, and establish a viable path toward heralded entanglement distribution
    and gate teleportation. Looking ahead, these results empower existing superconducting
    devices to take a key role in distributed quantum technologies and heterogeneous
    quantum systems.
acknowledgement: "We thank Fritz Diorico and Onur Hosten who suggested the filter
  cavity design, and gave important insights about the assembly and the testing of
  the FabryPerot filter cavities. Ekatrina Fedotova and Diego A.\r\nLancheros Naranjo
  worked on the filter cavity setup in\r\nthe early stages of this work. Gustavo Wiederhecker
  and\r\nYiewen Chu provided insights as to the origins of the\r\nobserved optical
  noise and Nicola Carlon Zambon suggested using telecom filters to mitigate it further.
  This\r\nwork was supported by the European Research Council under grant agreement
  no. 101089099 (ERC CoG\r\ncQEO), and 101248662 (ERC POC CoupledEOT), the\r\nEuropean
  Unions Horizon 2020 research and innovation\r\nprogram under grant agreement no.
  899354 (FETopen\r\nSuperQuLAN), the European Innovation Council no.\r\n101187231
  (PathfinderOpen CIELO), and the Austrian\r\nScience Fund (FWF) no. F7105 (SFB BeyondC).
  J.F.\r\nand L.K. acknowledge support from the Horizon Europe\r\nProgram HORIZON-CL4-2022-QUANTUM-01-SGA
  via\r\nProject No. 101113946 OpenSuperQPlus100. A.M. acknowledges support from the
  NOMIS-ISTA fellowship."
article_processing_charge: No
arxiv: 1
author:
- first_name: Thomas
  full_name: Werner, Thomas
  id: 1fcd8497-dba3-11ea-a45e-c6fbd715f7c7
  last_name: Werner
  orcid: 0009-0001-2346-5236
- first_name: Erfan
  full_name: Riyazi, Erfan
  id: 53322f94-5355-11ee-ae5a-ff6f81c87d51
  last_name: Riyazi
- first_name: Samarth
  full_name: Hawaldar, Samarth
  id: 221708e1-1ff6-11ee-9fa6-85146607433e
  last_name: Hawaldar
  orcid: 0000-0002-1965-4309
- first_name: Rishabh
  full_name: Sahu, Rishabh
  id: 47D26E34-F248-11E8-B48F-1D18A9856A87
  last_name: Sahu
  orcid: 0000-0001-6264-2162
- first_name: Georg M
  full_name: Arnold, Georg M
  id: 3770C838-F248-11E8-B48F-1D18A9856A87
  last_name: Arnold
  orcid: 0000-0003-1397-7876
- first_name: Paul Falthansl-Scheinecker
  full_name: Paul Falthansl-Scheinecker, Paul Falthansl-Scheinecker
  last_name: Paul Falthansl-Scheinecker
- first_name: Jennifer A. Sánchez
  full_name: Naranjo, Jennifer A. Sánchez
  last_name: Naranjo
- first_name: Dante
  full_name: Loi, Dante
  last_name: Loi
- first_name: Lucky N.
  full_name: Kapoor, Lucky N.
  last_name: Kapoor
- first_name: Martin
  full_name: Zemlicka, Martin
  id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87
  last_name: Zemlicka
  orcid: 0009-0005-0878-3032
- first_name: Liu
  full_name: Qiu, Liu
  id: 45e99c0d-1eb1-11eb-9b96-ed8ab2983cac
  last_name: Qiu
  orcid: 0000-0003-4345-4267
- first_name: Andrei
  full_name: Militaru, Andrei
  id: d67706f8-8eb1-11ee-ad1b-9c30dfa19e0b
  last_name: Militaru
- first_name: Johannes M
  full_name: Fink, Johannes M
  id: 4B591CBA-F248-11E8-B48F-1D18A9856A87
  last_name: Fink
  orcid: 0000-0001-8112-028X
citation:
  ama: Werner T, Riyazi E, Hawaldar S, et al. Electro-optic conversion of itinerant
    Fock states. <i>arXiv</i>. doi:<a href="https://doi.org/10.48550/arXiv.2602.00928">10.48550/arXiv.2602.00928</a>
  apa: Werner, T., Riyazi, E., Hawaldar, S., Sahu, R., Arnold, G. M., Paul Falthansl-Scheinecker,
    P. F.-S., … Fink, J. M. (n.d.). Electro-optic conversion of itinerant Fock states.
    <i>arXiv</i>. <a href="https://doi.org/10.48550/arXiv.2602.00928">https://doi.org/10.48550/arXiv.2602.00928</a>
  chicago: Werner, Thomas, Erfan Riyazi, Samarth Hawaldar, Rishabh Sahu, Georg M Arnold,
    Paul Falthansl-Scheinecker Paul Falthansl-Scheinecker, Jennifer A. Sánchez Naranjo,
    et al. “Electro-Optic Conversion of Itinerant Fock States.” <i>ArXiv</i>, n.d.
    <a href="https://doi.org/10.48550/arXiv.2602.00928">https://doi.org/10.48550/arXiv.2602.00928</a>.
  ieee: T. Werner <i>et al.</i>, “Electro-optic conversion of itinerant Fock states,”
    <i>arXiv</i>. .
  ista: Werner T, Riyazi E, Hawaldar S, Sahu R, Arnold GM, Paul Falthansl-Scheinecker
    PF-S, Naranjo JAS, Loi D, Kapoor LN, Zemlicka M, Qiu L, Militaru A, Fink JM. Electro-optic
    conversion of itinerant Fock states. arXiv, <a href="https://doi.org/10.48550/arXiv.2602.00928">10.48550/arXiv.2602.00928</a>.
  mla: Werner, Thomas, et al. “Electro-Optic Conversion of Itinerant Fock States.”
    <i>ArXiv</i>, doi:<a href="https://doi.org/10.48550/arXiv.2602.00928">10.48550/arXiv.2602.00928</a>.
  short: T. Werner, E. Riyazi, S. Hawaldar, R. Sahu, G.M. Arnold, P.F.-S. Paul Falthansl-Scheinecker,
    J.A.S. Naranjo, D. Loi, L.N. Kapoor, M. Zemlicka, L. Qiu, A. Militaru, J.M. Fink,
    ArXiv (n.d.).
corr_author: '1'
date_created: 2026-05-12T13:58:18Z
date_published: 2026-01-31T00:00:00Z
date_updated: 2026-05-20T13:35:42Z
day: '31'
department:
- _id: JoFi
- _id: GradSch
doi: 10.48550/arXiv.2602.00928
ec_funded: 1
external_id:
  arxiv:
  - '2602.00928'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.48550/arXiv.2602.00928
month: '01'
oa: 1
oa_version: Preprint
project:
- _id: bdadfa0d-d553-11ed-ba76-fb85edbd456a
  grant_number: '101089099'
  name: 'Cavity Quantum Electro Optics: Microwave photonics with nonclassical states'
- _id: 5b807754-ab3d-11f0-914f-ff8c34502cc9
  grant_number: '101248662'
  name: Integrated optical coupling for low loss electro-optic interconnects
- _id: 9B868D20-BA93-11EA-9121-9846C619BF3A
  call_identifier: H2020
  grant_number: '899354'
  name: Quantum Local Area Networks with Superconducting Qubits
- _id: 91aaf765-16d5-11f0-9cad-a8e7e44cccb7
  grant_number: '101187231'
  name: 'Cavity-Integrated Electro-Optics: Measuring, Converting and Manipulating
    Microwaves with Light'
- _id: 26927A52-B435-11E9-9278-68D0E5697425
  call_identifier: FWF
  grant_number: F07105
  name: Integrating superconducting quantum circuits
- _id: 9B861AAC-BA93-11EA-9121-9846C619BF3A
  name: NOMIS Fellowship Program
publication: arXiv
publication_status: draft
related_material:
  record:
  - id: '21863'
    relation: dissertation_contains
    status: public
scopus_import: '1'
status: public
title: Electro-optic conversion of itinerant Fock states
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: preprint
user_id: 8b945eb4-e2f2-11eb-945a-df72226e66a9
year: '2026'
...