[{"date_updated":"2026-05-20T13:35:42Z","_id":"21870","month":"01","doi":"10.48550/arXiv.2602.00928","arxiv":1,"article_processing_charge":"No","type":"preprint","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","status":"public","main_file_link":[{"open_access":"1","url":"https://doi.org/10.48550/arXiv.2602.00928"}],"OA_type":"green","date_published":"2026-01-31T00:00:00Z","related_material":{"record":[{"id":"21863","status":"public","relation":"dissertation_contains"}]},"project":[{"_id":"bdadfa0d-d553-11ed-ba76-fb85edbd456a","name":"Cavity Quantum Electro Optics: Microwave photonics with nonclassical states","grant_number":"101089099"},{"grant_number":"101248662","name":"Integrated optical coupling for low loss electro-optic interconnects","_id":"5b807754-ab3d-11f0-914f-ff8c34502cc9"},{"_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","grant_number":"F07105","call_identifier":"FWF","name":"Integrating superconducting quantum circuits"},{"name":"NOMIS Fellowship Program","_id":"9B861AAC-BA93-11EA-9121-9846C619BF3A"}],"ec_funded":1,"publication_status":"draft","corr_author":"1","external_id":{"arxiv":["2602.00928"]},"publication":"arXiv","day":"31","language":[{"iso":"eng"}],"scopus_import":"1","oa_version":"Preprint","oa":1,"OA_place":"repository","year":"2026","tmp":{"legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"date_created":"2026-05-12T13:58:18Z","abstract":[{"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.","lang":"eng"}],"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.","department":[{"_id":"JoFi"},{"_id":"GradSch"}],"title":"Electro-optic conversion of itinerant Fock states","citation":{"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>.","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>","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>.","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.).","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>.","ieee":"T. Werner <i>et al.</i>, “Electro-optic conversion of itinerant Fock states,” <i>arXiv</i>. .","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>"},"author":[{"id":"1fcd8497-dba3-11ea-a45e-c6fbd715f7c7","first_name":"Thomas","orcid":"0009-0001-2346-5236","last_name":"Werner","full_name":"Werner, Thomas"},{"id":"53322f94-5355-11ee-ae5a-ff6f81c87d51","first_name":"Erfan","last_name":"Riyazi","full_name":"Riyazi, Erfan"},{"last_name":"Hawaldar","full_name":"Hawaldar, Samarth","first_name":"Samarth","id":"221708e1-1ff6-11ee-9fa6-85146607433e","orcid":"0000-0002-1965-4309"},{"orcid":"0000-0001-6264-2162","id":"47D26E34-F248-11E8-B48F-1D18A9856A87","first_name":"Rishabh","full_name":"Sahu, Rishabh","last_name":"Sahu"},{"last_name":"Arnold","full_name":"Arnold, Georg M","id":"3770C838-F248-11E8-B48F-1D18A9856A87","first_name":"Georg M","orcid":"0000-0003-1397-7876"},{"first_name":"Paul Falthansl-Scheinecker","last_name":"Paul Falthansl-Scheinecker","full_name":"Paul Falthansl-Scheinecker, Paul Falthansl-Scheinecker"},{"full_name":"Naranjo, Jennifer A. Sánchez","last_name":"Naranjo","first_name":"Jennifer A. Sánchez"},{"first_name":"Dante","full_name":"Loi, Dante","last_name":"Loi"},{"full_name":"Kapoor, Lucky N.","last_name":"Kapoor","first_name":"Lucky N."},{"orcid":"0009-0005-0878-3032","first_name":"Martin","id":"2DCF8DE6-F248-11E8-B48F-1D18A9856A87","full_name":"Zemlicka, Martin","last_name":"Zemlicka"},{"last_name":"Qiu","full_name":"Qiu, Liu","id":"45e99c0d-1eb1-11eb-9b96-ed8ab2983cac","first_name":"Liu","orcid":"0000-0003-4345-4267"},{"first_name":"Andrei","id":"d67706f8-8eb1-11ee-ad1b-9c30dfa19e0b","full_name":"Militaru, Andrei","last_name":"Militaru"},{"orcid":"0000-0001-8112-028X","id":"4B591CBA-F248-11E8-B48F-1D18A9856A87","first_name":"Johannes M","full_name":"Fink, Johannes M","last_name":"Fink"}]}]