--- APC_amount: 6828 EUR DOAJ_listed: '1' OA_place: publisher OA_type: gold _id: '17202' abstract: - lang: eng text: Gate-tunable transmons (gatemons) employing semiconductor Josephson junctions have recently emerged as building blocks for hybrid quantum circuits. In this study, we present a gatemon fabricated in planar Germanium. We induce superconductivity in a two-dimensional hole gas by evaporating aluminum atop a thin spacer, which separates the superconductor from the Ge quantum well. The Josephson junction is then integrated into an Xmon circuit and capacitively coupled to a transmission line resonator. We showcase the qubit tunability in a broad frequency range with resonator and two-tone spectroscopy. Time-domain characterizations reveal energy relaxation and coherence times up to 75 ns. Our results, combined with the recent advances in the spin qubit field, pave the way towards novel hybrid and protected qubits in a group IV, CMOS-compatible material. acknowledged_ssus: - _id: ScienComp - _id: M-Shop - _id: NanoFab acknowledgement: "We acknowledge Lucas Casparis, Jeroen Danon, Valla Fatemi, Morten Kjaergard and Javad Shabani for their valuable insights and comments. This research was supported by the Scientific Service Units of ISTA through resources provided by the MIBA Machine Shop\r\nand the Nanofabrication facility. This research and related results were made possible with the support of the NOMIS Foundation and the FWF Projects with DOI:10.55776/I5060 and DOI:10.55776/P36507. We also acknowledge the NextGenerationEU PRIN project\r\n2022A8CJP3 (GAMESQUAD) for partial financial support." article_number: '6400' article_processing_charge: Yes article_type: original arxiv: 1 author: - first_name: Oliver full_name: Sagi, Oliver id: 71616374-A8E9-11E9-A7CA-09ECE5697425 last_name: Sagi - first_name: Alessandro full_name: Crippa, Alessandro id: 1F2B21A2-F6E7-11E9-9B82-F7DBE5697425 last_name: Crippa orcid: 0000-0002-2968-611X - first_name: Marco full_name: Valentini, Marco id: C0BB2FAC-D767-11E9-B658-BC13E6697425 last_name: Valentini - first_name: Marian full_name: Janik, Marian id: 396A1950-F248-11E8-B48F-1D18A9856A87 last_name: Janik orcid: 0009-0003-9037-8831 - first_name: Levon full_name: Baghumyan, Levon id: 7aa1f788-b527-11ee-aa9e-e6111a79e0c7 last_name: Baghumyan - first_name: Giorgio full_name: Fabris, Giorgio id: 298cf6f3-1ff6-11ee-9fa6-d94cfa0b3352 last_name: Fabris - first_name: Lucky full_name: Kapoor, Lucky id: 84b9700b-15b2-11ec-abd3-831089e67615 last_name: Kapoor orcid: 0000-0001-8319-2148 - first_name: Farid full_name: Hassani, Farid id: 2AED110C-F248-11E8-B48F-1D18A9856A87 last_name: Hassani orcid: 0000-0001-6937-5773 - first_name: Johannes M full_name: Fink, Johannes M id: 4B591CBA-F248-11E8-B48F-1D18A9856A87 last_name: Fink orcid: 0000-0001-8112-028X - first_name: Stefano full_name: Calcaterra, Stefano last_name: Calcaterra - first_name: Daniel full_name: Chrastina, Daniel last_name: Chrastina - first_name: Giovanni full_name: Isella, Giovanni last_name: Isella - first_name: Georgios full_name: Katsaros, Georgios id: 38DB5788-F248-11E8-B48F-1D18A9856A87 last_name: Katsaros orcid: 0000-0001-8342-202X citation: ama: Sagi O, Crippa A, Valentini M, et al. A gate tunable transmon qubit in planar Ge. Nature Communications. 2024;15. doi:10.1038/s41467-024-50763-6 apa: Sagi, O., Crippa, A., Valentini, M., Janik, M., Baghumyan, L., Fabris, G., … Katsaros, G. (2024). A gate tunable transmon qubit in planar Ge. Nature Communications. Springer Nature. https://doi.org/10.1038/s41467-024-50763-6 chicago: Sagi, Oliver, Alessandro Crippa, Marco Valentini, Marian Janik, Levon Baghumyan, Giorgio Fabris, Lucky Kapoor, et al. “A Gate Tunable Transmon Qubit in Planar Ge.” Nature Communications. Springer Nature, 2024. https://doi.org/10.1038/s41467-024-50763-6. ieee: O. Sagi et al., “A gate tunable transmon qubit in planar Ge,” Nature Communications, vol. 15. Springer Nature, 2024. ista: Sagi O, Crippa A, Valentini M, Janik M, Baghumyan L, Fabris G, Kapoor L, Hassani F, Fink JM, Calcaterra S, Chrastina D, Isella G, Katsaros G. 2024. A gate tunable transmon qubit in planar Ge. Nature Communications. 15, 6400. mla: Sagi, Oliver, et al. “A Gate Tunable Transmon Qubit in Planar Ge.” Nature Communications, vol. 15, 6400, Springer Nature, 2024, doi:10.1038/s41467-024-50763-6. short: O. Sagi, A. Crippa, M. Valentini, M. Janik, L. Baghumyan, G. Fabris, L. Kapoor, F. Hassani, J.M. Fink, S. Calcaterra, D. Chrastina, G. Isella, G. Katsaros, Nature Communications 15 (2024). corr_author: '1' date_created: 2024-07-04T11:40:45Z date_published: 2024-07-30T00:00:00Z date_updated: 2026-04-07T13:01:55Z day: '30' ddc: - '530' department: - _id: GeKa - _id: JoFi - _id: GradSch doi: 10.1038/s41467-024-50763-6 external_id: arxiv: - '2403.16774' isi: - '001281271000022' pmid: - '39080279' file: - access_level: open_access checksum: ddf5361dcb6c543e2cea818501c09910 content_type: application/pdf creator: dernst date_created: 2024-08-05T08:38:01Z date_updated: 2024-08-05T08:38:01Z file_id: '17388' file_name: 2024_NatureComm_Sagi.pdf file_size: 1928001 relation: main_file success: 1 file_date_updated: 2024-08-05T08:38:01Z has_accepted_license: '1' intvolume: ' 15' isi: 1 language: - iso: eng license: https://creativecommons.org/licenses/by/4.0/ month: '07' oa: 1 oa_version: Published Version pmid: 1 project: - _id: bd8bd29e-d553-11ed-ba76-f0070d4b237a grant_number: P36507 name: Merging spin and superconducting qubits in planar Ge - _id: c0977eea-5a5b-11eb-8a69-a862db0cf4d1 grant_number: I05060 name: High impedance circuit quantum electrodynamics with hole spins - _id: 262116AA-B435-11E9-9278-68D0E5697425 name: Hybrid Semiconductor - Superconductor Quantum Devices - _id: 3AC91DDA-15DF-11EA-824D-93A3E7B544D1 call_identifier: FWF name: FWF Open Access Fund publication: Nature Communications publication_identifier: eissn: - 2041-1723 publication_status: published publisher: Springer Nature quality_controlled: '1' related_material: link: - relation: erratum url: https://doi.org/10.1038/s41467-024-53910-1 record: - id: '17196' relation: research_data status: public - id: '18076' relation: dissertation_contains status: public scopus_import: '1' status: public title: A gate tunable transmon qubit in planar Ge 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: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 15 year: '2024' ... --- _id: '17410' abstract: - lang: eng text: We present a cavity-electromechanical system comprising a superconducting quantum interference device which is embedded in a microwave resonator and coupled via a pickup loop to a 6-μ⁢g magnetically levitated superconducting sphere. The motion of the sphere in the magnetic trap induces a frequency shift in the SQUID-cavity system. We use microwave spectroscopy to characterize the system, and we demonstrate that the electromechanical interaction is tunable. The measured displacement sensitivity of 10−7m/√Hz defines a path towards ground-state cooling of levitated particles with Planck-scale masses at millikelvin environment temperatures. acknowledgement: We gratefully acknowledge valuable discussions with Uros Delic, Lorenzo Magrini, and Corentin Gut. This work was supported by the European Union’s Horizon 2020 research and innovation program under Grant No. 863132 (iQLev) and No. 101080143 (SuperMeQ), the European Research Council under Grant No. 951234 (ERC Synergy QXtreme), the Austrian and Bavarian Academy of Sciences (Topical Team SGQ), the Alexander von Humboldt Foundation through a Feodor Lynen Fellowship (P.S.), the Swedish Research Council under Grant No. 2020-00381 (G.H.), and the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) via Germany’s Excellence Strategy EXC-2111-390814868 (H.H., R.G.). article_number: '014078' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Philip full_name: Schmidt, Philip last_name: Schmidt - first_name: Remi full_name: Claessen, Remi last_name: Claessen - first_name: Gerard full_name: Higgins, Gerard last_name: Higgins - first_name: Joachim full_name: Hofer, Joachim last_name: Hofer - first_name: Jannek J. full_name: Hansen, Jannek J. last_name: Hansen - first_name: Peter full_name: Asenbaum, Peter last_name: Asenbaum - first_name: Martin full_name: Zemlicka, Martin id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87 last_name: Zemlicka - first_name: Kevin full_name: Uhl, Kevin last_name: Uhl - first_name: Reinhold full_name: Kleiner, Reinhold last_name: Kleiner - first_name: Rudolf full_name: Gross, Rudolf last_name: Gross - first_name: Hans full_name: Huebl, Hans last_name: Huebl - first_name: Michael full_name: Trupke, Michael last_name: Trupke - first_name: Markus full_name: Aspelmeyer, Markus last_name: Aspelmeyer citation: ama: Schmidt P, Claessen R, Higgins G, et al. Remote sensing of a levitated superconductor with a flux-tunable microwave cavity. Physical Review Applied. 2024;22. doi:10.1103/PhysRevApplied.22.014078 apa: Schmidt, P., Claessen, R., Higgins, G., Hofer, J., Hansen, J. J., Asenbaum, P., … Aspelmeyer, M. (2024). Remote sensing of a levitated superconductor with a flux-tunable microwave cavity. Physical Review Applied. American Physical Society. https://doi.org/10.1103/PhysRevApplied.22.014078 chicago: Schmidt, Philip, Remi Claessen, Gerard Higgins, Joachim Hofer, Jannek J. Hansen, Peter Asenbaum, Martin Zemlicka, et al. “Remote Sensing of a Levitated Superconductor with a Flux-Tunable Microwave Cavity.” Physical Review Applied. American Physical Society, 2024. https://doi.org/10.1103/PhysRevApplied.22.014078. ieee: P. Schmidt et al., “Remote sensing of a levitated superconductor with a flux-tunable microwave cavity,” Physical Review Applied, vol. 22. American Physical Society, 2024. ista: Schmidt P, Claessen R, Higgins G, Hofer J, Hansen JJ, Asenbaum P, Zemlicka M, Uhl K, Kleiner R, Gross R, Huebl H, Trupke M, Aspelmeyer M. 2024. Remote sensing of a levitated superconductor with a flux-tunable microwave cavity. Physical Review Applied. 22, 014078. mla: Schmidt, Philip, et al. “Remote Sensing of a Levitated Superconductor with a Flux-Tunable Microwave Cavity.” Physical Review Applied, vol. 22, 014078, American Physical Society, 2024, doi:10.1103/PhysRevApplied.22.014078. short: P. Schmidt, R. Claessen, G. Higgins, J. Hofer, J.J. Hansen, P. Asenbaum, M. Zemlicka, K. Uhl, R. Kleiner, R. Gross, H. Huebl, M. Trupke, M. Aspelmeyer, Physical Review Applied 22 (2024). date_created: 2024-08-11T22:01:12Z date_published: 2024-07-30T00:00:00Z date_updated: 2025-09-08T08:50:31Z day: '30' department: - _id: JoFi doi: 10.1103/PhysRevApplied.22.014078 external_id: arxiv: - '2401.08854' isi: - '001284571700002' intvolume: ' 22' isi: 1 language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2401.08854 month: '07' oa: 1 oa_version: Preprint publication: Physical Review Applied publication_identifier: eissn: - 2331-7019 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Remote sensing of a levitated superconductor with a flux-tunable microwave cavity type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 22 year: '2024' ... --- DOAJ_listed: '1' _id: '17477' abstract: - lang: eng text: Trapped-ion systems are a leading platform for quantum information processing, but they are currently limited to 1D and 2D arrays, which imposes restrictions on both their scalability and their range of applications. Here, we propose a path to overcome this limitation by demonstrating that Penning traps can be used to realize remarkably clean bilayer crystals, wherein hundreds of ions self-organize into two well-defined layers. These bilayer crystals are made possible by the inclusion of an anharmonic trapping potential, which is readily implementable with current technology. We study the normal modes of this system and discover salient differences compared to the modes of single-plane crystals. The bilayer geometry and the unique properties of the normal modes open new opportunities—in particular, in quantum sensing and quantum simulation—that are not straightforward in single-plane crystals. Furthermore, we illustrate that it may be possible to extend the ideas presented here to realize multilayer crystals with more than two layers. Our work increases the dimensionality of trapped-ion systems by efficiently utilizing all three spatial dimensions, and it lays the foundation for a new generation of quantum information processing experiments with multilayer 3D crystals of trapped ions. acknowledgement: We thank M. Miskeen Khan, Jennifer Lilieholm, and Wes Johnson for a careful reading and feedback on the manuscript. We acknowledge discussions with Dan Dubin, John Zaris, and Scott Parker. S. H. acknowledges the support of Kishore Vaigyanik Protsahan Yojana, Department of Science and Technology, Government of India. A. S. acknowledges the support of a C. V. Raman post-doctoral fellowship. A. L. C., A. M. R., and J. J. B. acknowledge funding from the U.S. Department of Energy, Office of Science, NQI Science Research Centers, Quantum Systems Accelerator (QSA), a collaboration between the U.S. Department of Energy, Office of Science and other agencies. A. M. R. acknowledges additional support from VBFF, ARO Grant No. W911NF-24-1-0128, by the NSF Grants No. JILA-PFC PHY-2317149 and No. QLCI-OMA-2016244, and by NIST. J. J. B. acknowledges additional support from the DARPA ONISQ program and AFOSR Grant No. FA9550-201-0019. article_number: '031030' article_processing_charge: Yes article_type: original arxiv: 1 author: - first_name: Samarth full_name: Hawaldar, Samarth id: 221708e1-1ff6-11ee-9fa6-85146607433e last_name: Hawaldar orcid: 0000-0002-1965-4309 - first_name: Prakriti full_name: Shahi, Prakriti last_name: Shahi - first_name: Allison L. full_name: Carter, Allison L. last_name: Carter - first_name: Ana Maria full_name: Rey, Ana Maria last_name: Rey - first_name: John J. full_name: Bollinger, John J. last_name: Bollinger - first_name: Athreya full_name: Shankar, Athreya last_name: Shankar citation: ama: Hawaldar S, Shahi P, Carter AL, Rey AM, Bollinger JJ, Shankar A. Bilayer crystals of trapped ions for quantum information processing. Physical Review X. 2024;14(3). doi:10.1103/PhysRevX.14.031030 apa: Hawaldar, S., Shahi, P., Carter, A. L., Rey, A. M., Bollinger, J. J., & Shankar, A. (2024). Bilayer crystals of trapped ions for quantum information processing. Physical Review X. American Physical Society. https://doi.org/10.1103/PhysRevX.14.031030 chicago: Hawaldar, Samarth, Prakriti Shahi, Allison L. Carter, Ana Maria Rey, John J. Bollinger, and Athreya Shankar. “Bilayer Crystals of Trapped Ions for Quantum Information Processing.” Physical Review X. American Physical Society, 2024. https://doi.org/10.1103/PhysRevX.14.031030. ieee: S. Hawaldar, P. Shahi, A. L. Carter, A. M. Rey, J. J. Bollinger, and A. Shankar, “Bilayer crystals of trapped ions for quantum information processing,” Physical Review X, vol. 14, no. 3. American Physical Society, 2024. ista: Hawaldar S, Shahi P, Carter AL, Rey AM, Bollinger JJ, Shankar A. 2024. Bilayer crystals of trapped ions for quantum information processing. Physical Review X. 14(3), 031030. mla: Hawaldar, Samarth, et al. “Bilayer Crystals of Trapped Ions for Quantum Information Processing.” Physical Review X, vol. 14, no. 3, 031030, American Physical Society, 2024, doi:10.1103/PhysRevX.14.031030. short: S. Hawaldar, P. Shahi, A.L. Carter, A.M. Rey, J.J. Bollinger, A. Shankar, Physical Review X 14 (2024). corr_author: '1' date_created: 2024-09-01T22:01:08Z date_published: 2024-08-16T00:00:00Z date_updated: 2025-09-08T09:07:29Z day: '16' ddc: - '530' department: - _id: JoFi doi: 10.1103/PhysRevX.14.031030 external_id: arxiv: - '2312.10681' isi: - '001293977800002' file: - access_level: open_access checksum: 5d39b7dda67fd7b9a960235f6f38e280 content_type: application/pdf creator: cchlebak date_created: 2024-09-06T09:43:53Z date_updated: 2024-09-06T09:43:53Z file_id: '17757' file_name: 2024_PhysRevX_Hawaldar.pdf file_size: 3909653 relation: main_file success: 1 file_date_updated: 2024-09-06T09:43:53Z has_accepted_license: '1' intvolume: ' 14' isi: 1 issue: '3' language: - iso: eng month: '08' oa: 1 oa_version: Published Version publication: Physical Review X publication_identifier: eissn: - 2160-3308 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Bilayer crystals of trapped ions for quantum information processing 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: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 14 year: '2024' ... --- OA_place: repository _id: '18144' abstract: - lang: eng text: "High kinetic inductance superconductors are gaining increasing interest for\r\nthe realisation of qubits, amplifiers and detectors. Moreover, thanks to their\r\nhigh impedance, quantum buses made of such materials enable large zero-point\r\nfluctuations of the voltage, boosting the coupling rates to spin and charge\r\nqubits. However, fully exploiting the potential of disordered or granular\r\nsuperconductors is challenging, as their inductance and, therefore, impedance\r\nat high values are difficult to control. Here we have integrated a granular\r\naluminium resonator, having a characteristic impedance exceeding the resistance\r\nquantum, with a germanium double quantum dot and demonstrate strong\r\ncharge-photon coupling with a rate of $g_\\text{c}/2\\pi= (566 \\pm 2)$ MHz. This\r\nwas achieved due to the realisation of a wireless ohmmeter, which allows\r\n\\emph{in situ} measurements during film deposition and, therefore, control of\r\nthe kinetic inductance of granular aluminium films. Reproducible fabrication of\r\ncircuits with impedances (inductances) exceeding 13 k$\\Omega$ (1 nH per square)\r\nis now possible. This broadly applicable method opens the path for novel qubits\r\nand high-fidelity, long-distance two-qubit gates." acknowledged_ssus: - _id: M-Shop - _id: NanoFab acknowledgement: "We acknowledge Franco De Palma, Mahya Khorramshahi, Fabian Oppliger, Thomas Reisinger, Pasquale Scarlino and Xiao Xue for helpful discussions. This research was supported by the Scientific Service Units of ISTA through resources provided by the MIBA Machine Shop and the Nanofabrication facility. This research and related results were made possible with the support of the NOMIS Foundation, the HORIZON-RIA 101069515 project, the FWF Projects with DOI:10.55776/P32235, DOI:10.55776/I5060 and DOI:10.55776/P36507. IMP acknowledges funding from the Deutsche Forschungsgemeinschaft (DFG – German Research Foundation) under project number 450396347 (GeHoldeQED). ICN2 acknowledges funding from Generalitat de Catalunya 2021SGR00457. We acknowledge support from CSIC Interdisciplinary Thematic Platform (PTI+) on Quantum Technologies (PTI-QTEP+). This research work has been funded by the European Commission – NextGenerationEU (Regulation EU 2020/2094), through CSIC’s\r\nQuantum Technologies Platform (QTEP). ICN2 is supported by the Severo Ochoa program from Spanish MCIN/AEI (Grant No.: CEX2021-001214-S) and is funded by the CERCA Programme/Generalitat de Catalunya. Part of the present work has been performed in the framework of Universitat Autònoma de Barcelona Materials Science PhD program. AGM has received funding from Grant RYC2021-033479-I funded by MCIN/AEI/10.13039/501100011033 and by European Union NextGenerationEU/PRTR. M.B. acknowledges support from SUR Generalitat de Catalunya and the EU Social Fund; project ref. 2020 FI 00103. The authors\r\nacknowledge the use of instrumentation and the technical advice provided by the Joint Electron Microscopy Center at ALBA (JEMCA). ICN2 acknowledges funding from Grant IU16-014206 (METCAM-FIB) funded by the European Union through the European Regional Development\r\nFund (ERDF), with the support of the Ministry of Research and Universities, Generalitat de Catalunya. ICN2 is a founding member of e-DREAM [60]." article_number: '2407.03079' article_processing_charge: No arxiv: 1 author: - first_name: Marian full_name: Janik, Marian id: 396A1950-F248-11E8-B48F-1D18A9856A87 last_name: Janik orcid: 0009-0003-9037-8831 - first_name: Kevin Etienne Robert full_name: Roux, Kevin Etienne Robert id: 53f93ea2-803f-11ed-ab7e-b283135794ef last_name: Roux - first_name: Carla N full_name: Borja Espinosa, Carla N id: 18777c01-896a-11ed-bdf8-e4851dc07d16 last_name: Borja Espinosa - first_name: Oliver full_name: Sagi, Oliver id: 71616374-A8E9-11E9-A7CA-09ECE5697425 last_name: Sagi - first_name: Abdulhamid full_name: Baghdadi, Abdulhamid id: 160D87FA-96B5-11E9-BF77-7626E6697425 last_name: Baghdadi - first_name: Thomas full_name: Adletzberger, Thomas id: 38756BB2-F248-11E8-B48F-1D18A9856A87 last_name: Adletzberger - first_name: Stefano full_name: Calcaterra, Stefano last_name: Calcaterra - first_name: Marc full_name: Botifoll, Marc last_name: Botifoll - first_name: Alba Garzón full_name: Manjón, Alba Garzón last_name: Manjón - first_name: Jordi full_name: Arbiol, Jordi last_name: Arbiol - first_name: Daniel full_name: Chrastina, Daniel last_name: Chrastina - first_name: Giovanni full_name: Isella, Giovanni last_name: Isella - first_name: Ioan M. full_name: Pop, Ioan M. last_name: Pop - first_name: Georgios full_name: Katsaros, Georgios id: 38DB5788-F248-11E8-B48F-1D18A9856A87 last_name: Katsaros orcid: 0000-0001-8342-202X citation: ama: Janik M, Roux KER, Borja Espinosa CN, et al. Strong charge-photon coupling in planar germanium enabled by granular  aluminium superinductors. arXiv. doi:10.48550/arXiv.2407.03079 apa: Janik, M., Roux, K. E. R., Borja Espinosa, C. N., Sagi, O., Baghdadi, A., Adletzberger, T., … Katsaros, G. (n.d.). Strong charge-photon coupling in planar germanium enabled by granular  aluminium superinductors. arXiv. https://doi.org/10.48550/arXiv.2407.03079 chicago: Janik, Marian, Kevin Etienne Robert Roux, Carla N Borja Espinosa, Oliver Sagi, Abdulhamid Baghdadi, Thomas Adletzberger, Stefano Calcaterra, et al. “Strong Charge-Photon Coupling in Planar Germanium Enabled by Granular  Aluminium Superinductors.” ArXiv, n.d. https://doi.org/10.48550/arXiv.2407.03079. ieee: M. Janik et al., “Strong charge-photon coupling in planar germanium enabled by granular  aluminium superinductors,” arXiv. . ista: Janik M, Roux KER, Borja Espinosa CN, Sagi O, Baghdadi A, Adletzberger T, Calcaterra S, Botifoll M, Manjón AG, Arbiol J, Chrastina D, Isella G, Pop IM, Katsaros G. Strong charge-photon coupling in planar germanium enabled by granular  aluminium superinductors. arXiv, 2407.03079. mla: Janik, Marian, et al. “Strong Charge-Photon Coupling in Planar Germanium Enabled by Granular  Aluminium Superinductors.” ArXiv, 2407.03079, doi:10.48550/arXiv.2407.03079. short: M. Janik, K.E.R. Roux, C.N. Borja Espinosa, O. Sagi, A. Baghdadi, T. Adletzberger, S. Calcaterra, M. Botifoll, A.G. Manjón, J. Arbiol, D. Chrastina, G. Isella, I.M. Pop, G. Katsaros, ArXiv (n.d.). corr_author: '1' date_created: 2024-09-26T09:50:43Z date_published: 2024-07-03T00:00:00Z date_updated: 2026-08-21T22:30:51Z day: '03' department: - _id: GeKa - _id: GradSch - _id: JoFi doi: 10.48550/arXiv.2407.03079 external_id: arxiv: - '2407.03079' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2407.03079 month: '07' oa: 1 oa_version: Preprint project: - _id: 34c0acea-11ca-11ed-8bc3-8775e10fd452 grant_number: '101069515' name: Integrated Germanium Quantum Technology - _id: 237B3DA4-32DE-11EA-91FC-C7463DDC885E call_identifier: FWF grant_number: P32235 name: Towards scalable hut wire quantum devices - _id: bd8bd29e-d553-11ed-ba76-f0070d4b237a grant_number: P36507 name: Merging spin and superconducting qubits in planar Ge - _id: c0977eea-5a5b-11eb-8a69-a862db0cf4d1 grant_number: I05060 name: High impedance circuit quantum electrodynamics with hole spins publication: arXiv publication_status: draft related_material: record: - id: '18886' relation: research_data status: public - id: '19401' relation: later_version status: public - id: '18129' relation: dissertation_contains status: public status: public title: Strong charge-photon coupling in planar germanium enabled by granular aluminium superinductors 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: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2024' ... --- APC_amount: 3782,54 DOAJ_listed: '1' OA_place: publisher OA_type: gold _id: '17183' abstract: - lang: eng text: "The photon blockade breakdown in a continuously driven cavity QED system has been proposed as a prime example for a first-order driven-dissipative quantum phase transition. However, the predicted scaling from a microscopic behavior—dominated by quantum fluctuations—to a macroscopic one—characterized by stable phases—and the associated exponents and phase diagram have not been observed so far. In this work we couple a single transmon qubit with a fixed coupling strength \U0001D454 to a superconducting cavity that is in situ bandwidth \U0001D705 tunable to controllably approach this thermodynamic limit. Even though the system remains microscopic, we observe its behavior becoming increasingly macroscopic as a function of \U0001D454/\U0001D705. For the highest realized \U0001D454/\U0001D705 of approximately 287, the system switches with a characteristic timescale as long as 6 s between a bright coherent state with approximately 8×103 intracavity photons and the vacuum state. This exceeds the microscopic timescales by 6 orders of magnitude and approaches the perfect hysteresis expected between two macroscopic attractors in the thermodynamic limit. These findings and interpretation are qualitatively supported by neoclassical theory and large-scale quantum-jump Monte Carlo simulations. Besides shedding more light on driven-dissipative physics in the limit of strong light-matter coupling, this system might also find applications in quantum sensing and metrology." acknowledged_ssus: - _id: M-Shop acknowledgement: This work has received funding from the Austrian Science Fund (FWF) through BeyondC (F7105) and the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 862644 (FETopen QUARTET). A.V. acknowledges support from the National Research, Development and Innovation Office of Hungary (NKFIH) within the Quantum Information National Laboratory of Hungary. The authors thank the MIBA workshop and the Institute of Science and Technology Austria nanofabrication facility for technical support. We are grateful to HUN-REN Cloud for providing us with suitable computational infrastructure for the simulations. article_number: '010327' article_processing_charge: Yes article_type: original arxiv: 1 author: - first_name: Riya full_name: Sett, Riya id: 2E6D040E-F248-11E8-B48F-1D18A9856A87 last_name: Sett orcid: 0000-0001-7641-8348 - first_name: Farid full_name: Hassani, Farid id: 2AED110C-F248-11E8-B48F-1D18A9856A87 last_name: Hassani orcid: 0000-0001-6937-5773 - first_name: Duc T full_name: Phan, Duc T id: 29C8C0B4-F248-11E8-B48F-1D18A9856A87 last_name: Phan - first_name: Shabir full_name: Barzanjeh, Shabir id: 2D25E1F6-F248-11E8-B48F-1D18A9856A87 last_name: Barzanjeh orcid: 0000-0003-0415-1423 - first_name: Andras full_name: Vukics, Andras last_name: Vukics - 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: Sett R, Hassani F, Phan DT, Barzanjeh S, Vukics A, Fink JM. Emergent macroscopic bistability induced by a single superconducting qubit. PRX Quantum. 2024;5(1). doi:10.1103/prxquantum.5.010327 apa: Sett, R., Hassani, F., Phan, D. T., Barzanjeh, S., Vukics, A., & Fink, J. M. (2024). Emergent macroscopic bistability induced by a single superconducting qubit. PRX Quantum. American Physical Society. https://doi.org/10.1103/prxquantum.5.010327 chicago: Sett, Riya, Farid Hassani, Duc T Phan, Shabir Barzanjeh, Andras Vukics, and Johannes M Fink. “Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit.” PRX Quantum. American Physical Society, 2024. https://doi.org/10.1103/prxquantum.5.010327. ieee: R. Sett, F. Hassani, D. T. Phan, S. Barzanjeh, A. Vukics, and J. M. Fink, “Emergent macroscopic bistability induced by a single superconducting qubit,” PRX Quantum, vol. 5, no. 1. American Physical Society, 2024. ista: Sett R, Hassani F, Phan DT, Barzanjeh S, Vukics A, Fink JM. 2024. Emergent macroscopic bistability induced by a single superconducting qubit. PRX Quantum. 5(1), 010327. mla: Sett, Riya, et al. “Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit.” PRX Quantum, vol. 5, no. 1, 010327, American Physical Society, 2024, doi:10.1103/prxquantum.5.010327. short: R. Sett, F. Hassani, D.T. Phan, S. Barzanjeh, A. Vukics, J.M. Fink, PRX Quantum 5 (2024). corr_author: '1' date_created: 2024-06-27T10:58:06Z date_published: 2024-02-16T00:00:00Z date_updated: 2026-08-21T22:31:12Z day: '16' ddc: - '530' department: - _id: JoFi - _id: AnHi doi: 10.1103/prxquantum.5.010327 ec_funded: 1 external_id: arxiv: - '2210.14182' isi: - '001171652500001' file: - access_level: open_access checksum: 0833880d47f74ad1deda93a1d8ffa5a7 content_type: application/pdf creator: cchlebak date_created: 2024-06-28T12:04:43Z date_updated: 2024-06-28T12:04:43Z file_id: '17185' file_name: 2024_PRXQuantum_Sett.pdf file_size: 1443351 relation: main_file success: 1 file_date_updated: 2024-06-28T12:04:43Z has_accepted_license: '1' intvolume: ' 5' isi: 1 issue: '1' language: - iso: eng month: '02' oa: 1 oa_version: Published Version project: - _id: 237CBA6C-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '862644' name: Quantum readout techniques and technologies - _id: 3AC91DDA-15DF-11EA-824D-93A3E7B544D1 call_identifier: FWF name: FWF Open Access Fund - _id: bdb108fd-d553-11ed-ba76-83dc74a9864f grant_number: F07105 name: QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits publication: PRX Quantum publication_identifier: eissn: - 2691-3399 publication_status: published publisher: American Physical Society quality_controlled: '1' related_material: record: - id: '18978' relation: research_data status: public - id: '19533' relation: dissertation_contains status: public scopus_import: '1' status: public title: Emergent macroscopic bistability induced by a single superconducting qubit 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: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 5 year: '2024' ... --- OA_place: repository OA_type: gold _id: '18978' abstract: - lang: eng text: "Data analysis files for the manuscript \"Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit\".\r\n\r\nThis contains the raw data and the data analysis files for generating the figures in the manuscript.\r\n\r\n Figure1 file - The raw data of cavity transmission spectra for 6 different kappas are there. They are fitted with input-output theory in the python file.\r\n Figure2 file - The raw data at 8 MHz kappa are included. all hte figures in figure 2 are generated in the python file\r\n Figure3 file - The raw data of PBB single shot measurements at all kappas are included. The detailed analysis and the Figure3 generated for the paper are all in the python analysis file. Also, thefiles containing the time-evolution of the intensity from Master Equation solution are included.\r\nFigure4 file - The raw data at 2.6 MHz for different drive detunings and the corresponding analyses are included. And the python file includes the analysis of the experimental data as well as approximate neoclassical equations solutions for 2-level and 3-level transmons are included. " article_processing_charge: No author: - first_name: Riya full_name: Sett, Riya id: 2E6D040E-F248-11E8-B48F-1D18A9856A87 last_name: Sett orcid: 0000-0001-7641-8348 - first_name: Farid full_name: Hassani, Farid id: 2AED110C-F248-11E8-B48F-1D18A9856A87 last_name: Hassani orcid: 0000-0001-6937-5773 - first_name: Duc T full_name: Phan, Duc T id: 29C8C0B4-F248-11E8-B48F-1D18A9856A87 last_name: Phan - first_name: Shabir full_name: Barzanjeh, Shabir id: 2D25E1F6-F248-11E8-B48F-1D18A9856A87 last_name: Barzanjeh orcid: 0000-0003-0415-1423 - first_name: Andras full_name: Vukics, Andras last_name: Vukics - 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: Sett R, Hassani F, Phan DT, Barzanjeh S, Vukics A, Fink JM. Data Analysis files for “Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit.” 2024. doi:10.5281/ZENODO.10518320 apa: Sett, R., Hassani, F., Phan, D. T., Barzanjeh, S., Vukics, A., & Fink, J. M. (2024). Data Analysis files for “Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit.” Zenodo. https://doi.org/10.5281/ZENODO.10518320 chicago: Sett, Riya, Farid Hassani, Duc T Phan, Shabir Barzanjeh, Andras Vukics, and Johannes M Fink. “Data Analysis Files for ‘Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit.’” Zenodo, 2024. https://doi.org/10.5281/ZENODO.10518320. ieee: R. Sett, F. Hassani, D. T. Phan, S. Barzanjeh, A. Vukics, and J. M. Fink, “Data Analysis files for ‘Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit.’” Zenodo, 2024. ista: Sett R, Hassani F, Phan DT, Barzanjeh S, Vukics A, Fink JM. 2024. Data Analysis files for ‘Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit’, Zenodo, 10.5281/ZENODO.10518320. mla: Sett, Riya, et al. Data Analysis Files for “Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit.” Zenodo, 2024, doi:10.5281/ZENODO.10518320. short: R. Sett, F. Hassani, D.T. Phan, S. Barzanjeh, A. Vukics, J.M. Fink, (2024). corr_author: '1' date_created: 2025-01-30T08:30:03Z date_published: 2024-01-16T00:00:00Z date_updated: 2026-08-21T22:31:11Z day: '16' ddc: - '530' department: - _id: JoFi - _id: AnHi doi: 10.5281/ZENODO.10518320 has_accepted_license: '1' main_file_link: - open_access: '1' url: https://doi.org/10.5281/zenodo.10518320 month: '01' oa: 1 oa_version: Published Version publisher: Zenodo related_material: record: - id: '17183' relation: used_in_publication status: public - id: '19533' relation: used_in_publication status: public status: public title: Data Analysis files for "Emergent Macroscopic Bistability Induced by a Single Superconducting Qubit" 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: research_data_reference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2024' ... --- _id: '12819' abstract: - lang: eng text: 'Reaching a high cavity population with a coherent pump in the strong-coupling regime of a single-atom laser is impossible due to the photon blockade effect. In this Letter, we experimentally demonstrate that in a single-atom maser based on a transmon strongly coupled to two resonators, it is possible to pump over a dozen photons into the system. The first high-quality resonator plays the role of a usual lasing cavity, and the second one presents a controlled dissipation channel, bolstering population inversion, and modifies the energy-level structure to lift the blockade. As confirmation of the lasing action, we observe conventional laser features such as a narrowing of the emission linewidth and external signal amplification. Additionally, we report unique single-atom features: self-quenching and several lasing thresholds.' acknowledgement: We thank N.N. Abramov for assistance with the experimental setup. The sample was fabricated using equipment of MIPT Shared Facilities Center. This research was supported by Russian Science Foundation, grant no. 21-72-30026. article_number: L031701 article_processing_charge: No article_type: letter_note arxiv: 1 author: - first_name: Alesya full_name: Sokolova, Alesya id: 2d0a0600-edfb-11eb-afb5-c0f5fa7f4f3a last_name: Sokolova orcid: 0000-0002-8308-4144 - first_name: D. A. full_name: Kalacheva, D. A. last_name: Kalacheva - first_name: G. P. full_name: Fedorov, G. P. last_name: Fedorov - first_name: O. V. full_name: Astafiev, O. V. last_name: Astafiev citation: ama: Sokolova A, Kalacheva DA, Fedorov GP, Astafiev OV. Overcoming photon blockade in a circuit-QED single-atom maser with engineered metastability and strong coupling. Physical Review A. 2023;107(3). doi:10.1103/PhysRevA.107.L031701 apa: Sokolova, A., Kalacheva, D. A., Fedorov, G. P., & Astafiev, O. V. (2023). Overcoming photon blockade in a circuit-QED single-atom maser with engineered metastability and strong coupling. Physical Review A. American Physical Society. https://doi.org/10.1103/PhysRevA.107.L031701 chicago: Sokolova, Alesya, D. A. Kalacheva, G. P. Fedorov, and O. V. Astafiev. “Overcoming Photon Blockade in a Circuit-QED Single-Atom Maser with Engineered Metastability and Strong Coupling.” Physical Review A. American Physical Society, 2023. https://doi.org/10.1103/PhysRevA.107.L031701. ieee: A. Sokolova, D. A. Kalacheva, G. P. Fedorov, and O. V. Astafiev, “Overcoming photon blockade in a circuit-QED single-atom maser with engineered metastability and strong coupling,” Physical Review A, vol. 107, no. 3. American Physical Society, 2023. ista: Sokolova A, Kalacheva DA, Fedorov GP, Astafiev OV. 2023. Overcoming photon blockade in a circuit-QED single-atom maser with engineered metastability and strong coupling. Physical Review A. 107(3), L031701. mla: Sokolova, Alesya, et al. “Overcoming Photon Blockade in a Circuit-QED Single-Atom Maser with Engineered Metastability and Strong Coupling.” Physical Review A, vol. 107, no. 3, L031701, American Physical Society, 2023, doi:10.1103/PhysRevA.107.L031701. short: A. Sokolova, D.A. Kalacheva, G.P. Fedorov, O.V. Astafiev, Physical Review A 107 (2023). date_created: 2023-04-09T22:01:00Z date_published: 2023-03-22T00:00:00Z date_updated: 2023-08-01T14:06:05Z day: '22' department: - _id: JoFi doi: 10.1103/PhysRevA.107.L031701 external_id: arxiv: - '2209.05165' isi: - '000957799000006' intvolume: ' 107' isi: 1 issue: '3' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2209.05165 month: '03' oa: 1 oa_version: Preprint publication: Physical Review A publication_identifier: eissn: - 2469-9934 issn: - 2469-9926 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Overcoming photon blockade in a circuit-QED single-atom maser with engineered metastability and strong coupling type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 107 year: '2023' ... --- OA_place: publisher _id: '12900' abstract: - lang: eng text: "About a 100 years ago, we discovered that our universe is inherently noisy, that is, measuring any physical quantity with a precision beyond a certain point is not possible because of an omnipresent inherent noise. We call this - the quantum noise. Certain physical processes allow this quantum noise to get correlated in conjugate physical variables. These quantum correlations can be used to go beyond the potential of our inherently noisy universe and obtain a quantum advantage over the classical applications. \r\n\r\nQuantum noise being inherent also means that, at the fundamental level, the physical quantities are not well defined and therefore, objects can stay in multiple states at the same time. For example, the position of a particle not being well defined means that the particle is in multiple positions at the same time. About 4 decades ago, we started exploring the possibility of using objects which can be in multiple states at the same time to increase the dimensionality in computation. Thus, the field of quantum computing was born. We discovered that using quantum entanglement, a property closely related to quantum correlations, can be used to speed up computation of certain problems, such as factorisation of large numbers, faster than any known classical algorithm. Thus began the pursuit to make quantum computers a reality. \r\n\r\nTill date, we have explored quantum control over many physical systems including photons, spins, atoms, ions and even simple circuits made up of superconducting material. However, there persists one ubiquitous theme. The more readily a system interacts with an external field or matter, the more easily we can control it. But this also means that such a system can easily interact with a noisy environment and quickly lose its coherence. Consequently, such systems like electron spins need to be protected from the environment to ensure the longevity of their coherence. Other systems like nuclear spins are naturally protected as they do not interact easily with the environment. But, due to the same reason, it is harder to interact with such systems. \r\n\r\nAfter decades of experimentation with various systems, we are convinced that no one type of quantum system would be the best for all the quantum applications. We would need hybrid systems which are all interconnected - much like the current internet where all sorts of devices can all talk to each other - but now for quantum devices. A quantum internet. \r\n\r\nOptical photons are the best contenders to carry information for the quantum internet. They can carry quantum information cheaply and without much loss - the same reasons which has made them the backbone of our current internet. Following this direction, many systems, like trapped ions, have already demonstrated successful quantum links over a large distances using optical photons. However, some of the most promising contenders for quantum computing which are based on microwave frequencies have been left behind. This is because high energy optical photons can adversely affect fragile low-energy microwave systems. \r\n\r\nIn this thesis, we present substantial progress on this missing quantum link between microwave and optics using electrooptical nonlinearities in lithium niobate. The nonlinearities are enhanced by using resonant cavities for all the involved modes leading to observation of strong direct coupling between optical and microwave frequencies. With this strong coupling we are not only able to achieve almost 100\\% internal conversion efficiency with low added noise, thus presenting a quantum-enabled transducer, but also we are able to observe novel effects such as cooling of a microwave mode using optics. The strong coupling regime also leads to direct observation of dynamical backaction effect between microwave and optical frequencies which are studied in detail here. Finally, we also report first observation of microwave-optics entanglement in form of two-mode squeezed vacuum squeezed 0.7dB below vacuum level. \r\nWith this new bridge between microwave and optics, the microwave-based quantum technologies can finally be a part of a quantum network which is based on optical photons - putting us one step closer to a future with quantum internet. " acknowledged_ssus: - _id: M-Shop - _id: SSU - _id: NanoFab alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Rishabh full_name: Sahu, Rishabh id: 47D26E34-F248-11E8-B48F-1D18A9856A87 last_name: Sahu orcid: 0000-0001-6264-2162 citation: ama: Sahu R. Cavity quantum electrooptics. 2023. doi:10.15479/at:ista:12900 apa: Sahu, R. (2023). Cavity quantum electrooptics. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:12900 chicago: Sahu, Rishabh. “Cavity Quantum Electrooptics.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:12900. ieee: R. Sahu, “Cavity quantum electrooptics,” Institute of Science and Technology Austria, 2023. ista: Sahu R. 2023. Cavity quantum electrooptics. Institute of Science and Technology Austria. mla: Sahu, Rishabh. Cavity Quantum Electrooptics. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:12900. short: R. Sahu, Cavity Quantum Electrooptics, Institute of Science and Technology Austria, 2023. corr_author: '1' date_created: 2023-05-05T11:08:50Z date_published: 2023-05-05T00:00:00Z date_updated: 2026-04-15T06:43:26Z day: '05' ddc: - '537' - '535' - '539' degree_awarded: PhD department: - _id: GradSch - _id: JoFi doi: 10.15479/at:ista:12900 ec_funded: 1 file: - access_level: closed checksum: 8cbdab9c37ee55e591092a6f66b272c4 content_type: application/x-zip-compressed creator: rsahu date_created: 2023-05-09T08:45:14Z date_updated: 2023-06-06T22:30:03Z embargo_to: open_access file_id: '12928' file_name: thesis.zip file_size: 36767177 relation: source_file - access_level: closed checksum: 439659ead46618147309be39d9dd5a8c content_type: application/pdf creator: rsahu date_created: 2023-05-09T08:51:17Z date_updated: 2023-07-06T11:37:40Z file_id: '12929' file_name: thesis_pdfa_final.pdf file_size: 17501990 relation: main_file file_date_updated: 2023-07-06T11:37:40Z has_accepted_license: '1' keyword: - quantum optics - electrooptics - quantum networks - quantum communication - transduction language: - iso: eng license: https://creativecommons.org/licenses/by-nc-sa/4.0/ month: '05' oa_version: Published Version page: '190' project: - _id: 26336814-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '758053' name: A Fiber Optic Transceiver for Superconducting Qubits - _id: 9B868D20-BA93-11EA-9121-9846C619BF3A call_identifier: H2020 grant_number: '899354' name: Quantum Local Area Networks with Superconducting Qubits - _id: bdb108fd-d553-11ed-ba76-83dc74a9864f grant_number: F07105 name: QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits publication_identifier: isbn: - 978-3-99078-030-5 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '13175' relation: new_edition status: public - id: '10924' relation: part_of_dissertation status: public - id: '9114' relation: part_of_dissertation status: public status: public supervisor: - first_name: Johannes M full_name: Fink, Johannes M id: 4B591CBA-F248-11E8-B48F-1D18A9856A87 last_name: Fink orcid: 0000-0001-8112-028X title: Cavity quantum electrooptics tmp: image: /images/cc_by_nc_sa.png legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) short: CC BY-NC-SA (4.0) type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ... --- _id: '13106' abstract: - lang: eng text: Quantum entanglement is a key resource in currently developed quantum technologies. Sharing this fragile property between superconducting microwave circuits and optical or atomic systems would enable new functionalities, but this has been hindered by an energy scale mismatch of >104 and the resulting mutually imposed loss and noise. In this work, we created and verified entanglement between microwave and optical fields in a millikelvin environment. Using an optically pulsed superconducting electro-optical device, we show entanglement between propagating microwave and optical fields in the continuous variable domain. This achievement not only paves the way for entanglement between superconducting circuits and telecom wavelength light, but also has wide-ranging implications for hybrid quantum networks in the context of modularization, scaling, sensing, and cross-platform verification. acknowledgement: This work was supported by the European Research Council (grant no. 758053, ERC StG QUNNECT) and the European Union’s Horizon 2020 Research and Innovation Program (grant no. 899354, FETopen SuperQuLAN). L.Q. acknowledges generous support from the ISTFELLOW program. W.H. is the recipient of an ISTplus postdoctoral fellowship with funding from the European Union’s Horizon 2020 Research and Innovation Program (Marie Sklodowska-Curie grant no. 754411). G.A. is the recipient of a DOC fellowship of the Austrian Academy of Sciences at IST Austria. J.M.F. acknowledges support from the Austrian Science Fund (FWF) through BeyondC (grant no. F7105) and the European Union’s Horizon 2020 Research and Innovation Program (grant no. 862644, FETopen QUARTET). article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Rishabh full_name: Sahu, Rishabh id: 47D26E34-F248-11E8-B48F-1D18A9856A87 last_name: Sahu orcid: 0000-0001-6264-2162 - first_name: Liu full_name: Qiu, Liu id: 45e99c0d-1eb1-11eb-9b96-ed8ab2983cac last_name: Qiu orcid: 0000-0003-4345-4267 - first_name: William J full_name: Hease, William J id: 29705398-F248-11E8-B48F-1D18A9856A87 last_name: Hease orcid: 0000-0001-9868-2166 - 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: Y. full_name: Minoguchi, Y. last_name: Minoguchi - first_name: P. full_name: Rabl, P. last_name: Rabl - 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: Sahu R, Qiu L, Hease WJ, et al. Entangling microwaves with light. Science. 2023;380(6646):718-721. doi:10.1126/science.adg3812 apa: Sahu, R., Qiu, L., Hease, W. J., Arnold, G. M., Minoguchi, Y., Rabl, P., & Fink, J. M. (2023). Entangling microwaves with light. Science. American Association for the Advancement of Science. https://doi.org/10.1126/science.adg3812 chicago: Sahu, Rishabh, Liu Qiu, William J Hease, Georg M Arnold, Y. Minoguchi, P. Rabl, and Johannes M Fink. “Entangling Microwaves with Light.” Science. American Association for the Advancement of Science, 2023. https://doi.org/10.1126/science.adg3812. ieee: R. Sahu et al., “Entangling microwaves with light,” Science, vol. 380, no. 6646. American Association for the Advancement of Science, pp. 718–721, 2023. ista: Sahu R, Qiu L, Hease WJ, Arnold GM, Minoguchi Y, Rabl P, Fink JM. 2023. Entangling microwaves with light. Science. 380(6646), 718–721. mla: Sahu, Rishabh, et al. “Entangling Microwaves with Light.” Science, vol. 380, no. 6646, American Association for the Advancement of Science, 2023, pp. 718–21, doi:10.1126/science.adg3812. short: R. Sahu, L. Qiu, W.J. Hease, G.M. Arnold, Y. Minoguchi, P. Rabl, J.M. Fink, Science 380 (2023) 718–721. corr_author: '1' date_created: 2023-05-31T11:39:24Z date_published: 2023-05-18T00:00:00Z date_updated: 2026-04-15T06:39:33Z day: '18' department: - _id: JoFi doi: 10.1126/science.adg3812 ec_funded: 1 external_id: arxiv: - '2301.03315' isi: - '000996515200004' pmid: - '37200415' intvolume: ' 380' isi: 1 issue: '6646' keyword: - Multidisciplinary language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2301.03315 month: '05' oa: 1 oa_version: Preprint page: 718-721 pmid: 1 project: - _id: 26336814-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '758053' name: A Fiber Optic Transceiver for Superconducting Qubits - _id: 9B868D20-BA93-11EA-9121-9846C619BF3A call_identifier: H2020 grant_number: '899354' name: Quantum Local Area Networks with Superconducting Qubits - _id: 260C2330-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '754411' name: ISTplus - Postdoctoral Fellowships - _id: 237CBA6C-32DE-11EA-91FC-C7463DDC885E call_identifier: H2020 grant_number: '862644' name: Quantum readout techniques and technologies - _id: 2671EB66-B435-11E9-9278-68D0E5697425 name: Coherent on-chip conversion of superconducting qubit signals from microwaves to optical frequencies - _id: bdb108fd-d553-11ed-ba76-83dc74a9864f grant_number: F07105 name: QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits publication: Science publication_identifier: eissn: - 1095-9203 issn: - 0036-8075 publication_status: published publisher: American Association for the Advancement of Science quality_controlled: '1' related_material: link: - description: News on ISTA Website relation: press_release url: https://ista.ac.at/en/news/wiring-up-quantum-circuits-with-light/ record: - id: '13122' relation: research_data status: public scopus_import: '1' status: public title: Entangling microwaves with light type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 380 year: '2023' ... --- _id: '13122' abstract: - lang: eng text: Data for submitted article "Entangling microwaves with light" at arXiv:2301.03315v1 article_processing_charge: No author: - first_name: Rishabh full_name: Sahu, Rishabh id: 47D26E34-F248-11E8-B48F-1D18A9856A87 last_name: Sahu orcid: 0000-0001-6264-2162 citation: ama: Sahu R. Entangling microwaves with light. 2023. doi:10.5281/ZENODO.7789417 apa: Sahu, R. (2023). Entangling microwaves with light. Zenodo. https://doi.org/10.5281/ZENODO.7789417 chicago: Sahu, Rishabh. “Entangling Microwaves with Light.” Zenodo, 2023. https://doi.org/10.5281/ZENODO.7789417. ieee: R. Sahu, “Entangling microwaves with light.” Zenodo, 2023. ista: Sahu R. 2023. Entangling microwaves with light, Zenodo, 10.5281/ZENODO.7789417. mla: Sahu, Rishabh. Entangling Microwaves with Light. Zenodo, 2023, doi:10.5281/ZENODO.7789417. short: R. Sahu, (2023). corr_author: '1' date_created: 2023-06-06T06:46:16Z date_published: 2023-03-31T00:00:00Z date_updated: 2026-04-15T06:39:32Z day: '31' department: - _id: JoFi doi: 10.5281/ZENODO.7789417 main_file_link: - open_access: '1' url: https://doi.org/10.5281/zenodo.7789418 month: '03' oa: 1 oa_version: Published Version publisher: Zenodo related_material: record: - id: '13106' relation: used_in_publication status: public status: public title: Entangling microwaves with light 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: research_data_reference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2023' ... --- _id: '13124' abstract: - lang: eng text: This dataset comprises all data shown in the figures of the submitted article "Tunable directional photon scattering from a pair of superconducting qubits" at arXiv:2205.03293. Additional raw data are available from the corresponding author on reasonable request. article_processing_charge: No author: - first_name: Elena full_name: Redchenko, Elena id: 2C21D6E8-F248-11E8-B48F-1D18A9856A87 last_name: Redchenko - first_name: Alexander full_name: Poshakinskiy, Alexander last_name: Poshakinskiy - first_name: Riya full_name: Sett, Riya id: 2E6D040E-F248-11E8-B48F-1D18A9856A87 last_name: Sett orcid: 0000-0001-7641-8348 - first_name: Martin full_name: Zemlicka, Martin id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87 last_name: Zemlicka orcid: 0009-0005-0878-3032 - first_name: Alexander full_name: Poddubny, Alexander last_name: Poddubny - 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: Redchenko E, Poshakinskiy A, Sett R, Zemlicka M, Poddubny A, Fink JM. Tunable directional photon scattering from a pair of superconducting qubits. 2023. doi:10.5281/ZENODO.7858567 apa: Redchenko, E., Poshakinskiy, A., Sett, R., Zemlicka, M., Poddubny, A., & Fink, J. M. (2023). Tunable directional photon scattering from a pair of superconducting qubits. Zenodo. https://doi.org/10.5281/ZENODO.7858567 chicago: Redchenko, Elena, Alexander Poshakinskiy, Riya Sett, Martin Zemlicka, Alexander Poddubny, and Johannes M Fink. “Tunable Directional Photon Scattering from a Pair of Superconducting Qubits.” Zenodo, 2023. https://doi.org/10.5281/ZENODO.7858567. ieee: E. Redchenko, A. Poshakinskiy, R. Sett, M. Zemlicka, A. Poddubny, and J. M. Fink, “Tunable directional photon scattering from a pair of superconducting qubits.” Zenodo, 2023. ista: Redchenko E, Poshakinskiy A, Sett R, Zemlicka M, Poddubny A, Fink JM. 2023. Tunable directional photon scattering from a pair of superconducting qubits, Zenodo, 10.5281/ZENODO.7858567. mla: Redchenko, Elena, et al. Tunable Directional Photon Scattering from a Pair of Superconducting Qubits. Zenodo, 2023, doi:10.5281/ZENODO.7858567. short: E. Redchenko, A. Poshakinskiy, R. Sett, M. Zemlicka, A. Poddubny, J.M. Fink, (2023). corr_author: '1' date_created: 2023-06-06T07:36:50Z date_published: 2023-04-28T00:00:00Z date_updated: 2026-06-03T07:16:05Z day: '28' ddc: - '530' department: - _id: JoFi doi: 10.5281/ZENODO.7858567 main_file_link: - open_access: '1' url: https://doi.org/10.5281/zenodo.7858567 month: '04' oa: 1 oa_version: Published Version publisher: Zenodo related_material: record: - id: '13117' relation: used_in_publication status: public status: public title: Tunable directional photon scattering from a pair of superconducting qubits 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: research_data_reference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2023' ... --- OA_place: publisher _id: '13175' abstract: - lang: eng text: "About a 100 years ago, we discovered that our universe is inherently noisy, that is, measuring any physical quantity with a precision beyond a certain point is not possible because of an omnipresent inherent noise. We call this - the quantum noise. Certain physical processes allow this quantum noise to get correlated in conjugate physical variables. These quantum correlations can be used to go beyond the potential of our inherently noisy universe and obtain a quantum advantage over the classical applications. \r\n\r\nQuantum noise being inherent also means that, at the fundamental level, the physical quantities are not well defined and therefore, objects can stay in multiple states at the same time. For example, the position of a particle not being well defined means that the particle is in multiple positions at the same time. About 4 decades ago, we started exploring the possibility of using objects which can be in multiple states at the same time to increase the dimensionality in computation. Thus, the field of quantum computing was born. We discovered that using quantum entanglement, a property closely related to quantum correlations, can be used to speed up computation of certain problems, such as factorisation of large numbers, faster than any known classical algorithm. Thus began the pursuit to make quantum computers a reality. \r\n\r\nTill date, we have explored quantum control over many physical systems including photons, spins, atoms, ions and even simple circuits made up of superconducting material. However, there persists one ubiquitous theme. The more readily a system interacts with an external field or matter, the more easily we can control it. But this also means that such a system can easily interact with a noisy environment and quickly lose its coherence. Consequently, such systems like electron spins need to be protected from the environment to ensure the longevity of their coherence. Other systems like nuclear spins are naturally protected as they do not interact easily with the environment. But, due to the same reason, it is harder to interact with such systems. \r\n\r\nAfter decades of experimentation with various systems, we are convinced that no one type of quantum system would be the best for all the quantum applications. We would need hybrid systems which are all interconnected - much like the current internet where all sorts of devices can all talk to each other - but now for quantum devices. A quantum internet. \r\n\r\nOptical photons are the best contenders to carry information for the quantum internet. They can carry quantum information cheaply and without much loss - the same reasons which has made them the backbone of our current internet. Following this direction, many systems, like trapped ions, have already demonstrated successful quantum links over a large distances using optical photons. However, some of the most promising contenders for quantum computing which are based on microwave frequencies have been left behind. This is because high energy optical photons can adversely affect fragile low-energy microwave systems. \r\n\r\nIn this thesis, we present substantial progress on this missing quantum link between microwave and optics using electrooptical nonlinearities in lithium niobate. The nonlinearities are enhanced by using resonant cavities for all the involved modes leading to observation of strong direct coupling between optical and microwave frequencies. With this strong coupling we are not only able to achieve almost 100\\% internal conversion efficiency with low added noise, thus presenting a quantum-enabled transducer, but also we are able to observe novel effects such as cooling of a microwave mode using optics. The strong coupling regime also leads to direct observation of dynamical backaction effect between microwave and optical frequencies which are studied in detail here. Finally, we also report first observation of microwave-optics entanglement in form of two-mode squeezed vacuum squeezed 0.7dB below vacuum level. \r\nWith this new bridge between microwave and optics, the microwave-based quantum technologies can finally be a part of a quantum network which is based on optical photons - putting us one step closer to a future with quantum internet. " acknowledged_ssus: - _id: M-Shop - _id: SSU - _id: NanoFab alternative_title: - ISTA Thesis article_processing_charge: No author: - first_name: Rishabh full_name: Sahu, Rishabh id: 47D26E34-F248-11E8-B48F-1D18A9856A87 last_name: Sahu orcid: 0000-0001-6264-2162 citation: ama: Sahu R. Cavity quantum electrooptics. 2023. doi:10.15479/at:ista:13175 apa: Sahu, R. (2023). Cavity quantum electrooptics. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:13175 chicago: Sahu, Rishabh. “Cavity Quantum Electrooptics.” Institute of Science and Technology Austria, 2023. https://doi.org/10.15479/at:ista:13175. ieee: R. Sahu, “Cavity quantum electrooptics,” Institute of Science and Technology Austria, 2023. ista: Sahu R. 2023. Cavity quantum electrooptics. Institute of Science and Technology Austria. mla: Sahu, Rishabh. Cavity Quantum Electrooptics. Institute of Science and Technology Austria, 2023, doi:10.15479/at:ista:13175. short: R. Sahu, Cavity Quantum Electrooptics, Institute of Science and Technology Austria, 2023. corr_author: '1' date_created: 2023-06-30T08:07:43Z date_published: 2023-05-05T00:00:00Z date_updated: 2026-04-15T06:43:26Z day: '05' ddc: - '537' - '535' - '539' degree_awarded: PhD department: - _id: GradSch - _id: JoFi doi: 10.15479/at:ista:13175 ec_funded: 1 file: - access_level: open_access checksum: 7d03f1a5a5258ee43dfc3323dea4e08f content_type: application/pdf creator: cchlebak date_created: 2023-06-30T08:17:25Z date_updated: 2023-06-30T08:17:25Z file_id: '13176' file_name: thesis_pdfa.pdf file_size: 18688376 relation: main_file success: 1 - access_level: closed checksum: c3b45317ae58e0527533f98c202d81b7 content_type: application/x-zip-compressed creator: cchlebak date_created: 2023-07-06T11:35:15Z date_updated: 2023-07-06T11:35:15Z file_id: '13196' file_name: thesis.zip file_size: 37847025 relation: source_file file_date_updated: 2023-07-06T11:35:15Z has_accepted_license: '1' keyword: - quantum optics - electrooptics - quantum networks - quantum communication - transduction language: - iso: eng month: '05' oa: 1 oa_version: Published Version page: '202' project: - _id: 26336814-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '758053' name: A Fiber Optic Transceiver for Superconducting Qubits - _id: 9B868D20-BA93-11EA-9121-9846C619BF3A call_identifier: H2020 grant_number: '899354' name: Quantum Local Area Networks with Superconducting Qubits - _id: bdb108fd-d553-11ed-ba76-83dc74a9864f grant_number: F07105 name: QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits publication_identifier: isbn: - 978-3-99078-030-5 issn: - 2663-337X publication_status: published publisher: Institute of Science and Technology Austria related_material: record: - id: '12900' relation: old_edition status: public - id: '10924' relation: part_of_dissertation status: public - id: '9114' relation: part_of_dissertation status: public status: public supervisor: - first_name: Johannes M full_name: Fink, Johannes M id: 4B591CBA-F248-11E8-B48F-1D18A9856A87 last_name: Fink orcid: 0000-0001-8112-028X title: Cavity quantum electrooptics tmp: image: /images/cc_by_nc_sa.png legal_code_url: https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode name: Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) short: CC BY-NC-SA (4.0) type: dissertation user_id: ba8df636-2132-11f1-aed0-ed93e2281fdd year: '2023' ... --- _id: '13227' abstract: - lang: eng text: Currently available quantum processors are dominated by noise, which severely limits their applicability and motivates the search for new physical qubit encodings. In this work, we introduce the inductively shunted transmon, a weakly flux-tunable superconducting qubit that offers charge offset protection for all levels and a 20-fold reduction in flux dispersion compared to the state-of-the-art resulting in a constant coherence over a full flux quantum. The parabolic confinement provided by the inductive shunt as well as the linearity of the geometric superinductor facilitates a high-power readout that resolves quantum jumps with a fidelity and QND-ness of >90% and without the need for a Josephson parametric amplifier. Moreover, the device reveals quantum tunneling physics between the two prepared fluxon ground states with a measured average decay time of up to 3.5 h. In the future, fast time-domain control of the transition matrix elements could offer a new path forward to also achieve full qubit control in the decay-protected fluxon basis. acknowledged_ssus: - _id: M-Shop - _id: NanoFab acknowledgement: The authors thank J. Koch for discussions and support with the scQubits python package, I. Rozhansky and A. Poddubny for important insights into photon-assisted tunneling, S. Barzanjeh and G. Arnold for theory, E. Redchenko, S. Pepic, the MIBA workshop and the IST nanofabrication facility for technical contributions, as well as L. Drmic, P. Zielinski and R. Sett for software development. We acknowledge the prompt support of Quantum Machines to implement active state preparation with their OPX+. This work was supported by a NOMIS foundation research grant (J.F.), the Austrian Science Fund (FWF) through BeyondC F7105 (J.F.) and IST Austria. article_number: '3968' article_processing_charge: No article_type: original author: - first_name: Farid full_name: Hassani, Farid id: 2AED110C-F248-11E8-B48F-1D18A9856A87 last_name: Hassani orcid: 0000-0001-6937-5773 - first_name: Matilda full_name: Peruzzo, Matilda id: 3F920B30-F248-11E8-B48F-1D18A9856A87 last_name: Peruzzo orcid: 0000-0002-3415-4628 - first_name: Lucky full_name: Kapoor, Lucky id: 84b9700b-15b2-11ec-abd3-831089e67615 last_name: Kapoor orcid: 0000-0001-8319-2148 - first_name: Andrea full_name: Trioni, Andrea id: 42F71B44-F248-11E8-B48F-1D18A9856A87 last_name: Trioni - first_name: Martin full_name: Zemlicka, Martin id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87 last_name: Zemlicka orcid: 0009-0005-0878-3032 - 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: Hassani F, Peruzzo M, Kapoor L, Trioni A, Zemlicka M, Fink JM. Inductively shunted transmons exhibit noise insensitive plasmon states and a fluxon decay exceeding 3 hours. Nature Communications. 2023;14. doi:10.1038/s41467-023-39656-2 apa: Hassani, F., Peruzzo, M., Kapoor, L., Trioni, A., Zemlicka, M., & Fink, J. M. (2023). Inductively shunted transmons exhibit noise insensitive plasmon states and a fluxon decay exceeding 3 hours. Nature Communications. Springer Nature. https://doi.org/10.1038/s41467-023-39656-2 chicago: Hassani, Farid, Matilda Peruzzo, Lucky Kapoor, Andrea Trioni, Martin Zemlicka, and Johannes M Fink. “Inductively Shunted Transmons Exhibit Noise Insensitive Plasmon States and a Fluxon Decay Exceeding 3 Hours.” Nature Communications. Springer Nature, 2023. https://doi.org/10.1038/s41467-023-39656-2. ieee: F. Hassani, M. Peruzzo, L. Kapoor, A. Trioni, M. Zemlicka, and J. M. Fink, “Inductively shunted transmons exhibit noise insensitive plasmon states and a fluxon decay exceeding 3 hours,” Nature Communications, vol. 14. Springer Nature, 2023. ista: Hassani F, Peruzzo M, Kapoor L, Trioni A, Zemlicka M, Fink JM. 2023. Inductively shunted transmons exhibit noise insensitive plasmon states and a fluxon decay exceeding 3 hours. Nature Communications. 14, 3968. mla: Hassani, Farid, et al. “Inductively Shunted Transmons Exhibit Noise Insensitive Plasmon States and a Fluxon Decay Exceeding 3 Hours.” Nature Communications, vol. 14, 3968, Springer Nature, 2023, doi:10.1038/s41467-023-39656-2. short: F. Hassani, M. Peruzzo, L. Kapoor, A. Trioni, M. Zemlicka, J.M. Fink, Nature Communications 14 (2023). corr_author: '1' date_created: 2023-07-16T22:01:08Z date_published: 2023-07-05T00:00:00Z date_updated: 2026-04-15T06:39:57Z day: '05' ddc: - '530' department: - _id: JoFi doi: 10.1038/s41467-023-39656-2 external_id: isi: - '001024729900009' pmid: - '37407570' file: - access_level: open_access checksum: a85773b5fe23516f60f7d5d31b55c200 content_type: application/pdf creator: dernst date_created: 2023-07-18T08:43:07Z date_updated: 2023-07-18T08:43:07Z file_id: '13248' file_name: 2023_NatureComm_Hassani.pdf file_size: 2899592 relation: main_file success: 1 file_date_updated: 2023-07-18T08:43:07Z has_accepted_license: '1' intvolume: ' 14' isi: 1 language: - iso: eng month: '07' oa: 1 oa_version: Published Version pmid: 1 project: - _id: 2622978C-B435-11E9-9278-68D0E5697425 name: Hybrid Semiconductor - Superconductor Quantum Devices - _id: bdb108fd-d553-11ed-ba76-83dc74a9864f grant_number: F07105 name: QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits publication: Nature Communications publication_identifier: eissn: - 2041-1723 publication_status: published publisher: Springer Nature quality_controlled: '1' related_material: record: - id: '17133' relation: dissertation_contains status: public scopus_import: '1' status: public title: Inductively shunted transmons exhibit noise insensitive plasmon states and a fluxon decay exceeding 3 hours 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: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 14 year: '2023' ... --- _id: '14489' abstract: - lang: eng text: Microwave-optics entanglement is a vital component for building hybrid quantum networks. Here, a new mechanism for preparing stationary entanglement between microwave and optical cavity fields in a cavity optomagnomechanical system is proposed. It consists of a magnon mode in a ferrimagnetic crystal that couples directly to a microwave cavity mode via the magnetic dipole interaction and indirectly to an optical cavity through the deformation displacement of the crystal. The mechanical displacement is induced by the magnetostrictive force and coupled to the optical cavity via radiation pressure. Both the opto- and magnomechanical couplings are dispersive. Magnon–phonon entanglement is created via magnomechanical parametric down-conversion, which is further distributed to optical and microwave photons via simultaneous optomechanical beamsplitter interaction and electromagnonic state-swap interaction, yielding stationary microwave-optics entanglement. The microwave-optics entanglement is robust against thermal noise, which will find broad potential applications in quantum networks and quantum information processing with hybrid quantum systems. acknowledgement: This work was supported by the National Key Research and Development Program of China (Grant no. 2022YFA1405200), the National Natural Science Foundation of China (Nos. 92265202), and the European Research Council (ERC CoG Q-ECHOS, 101001005). article_number: '2200866' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Zhi Yuan full_name: Fan, Zhi Yuan last_name: Fan - first_name: Liu full_name: Qiu, Liu id: 45e99c0d-1eb1-11eb-9b96-ed8ab2983cac last_name: Qiu orcid: 0000-0003-4345-4267 - first_name: Simon full_name: Gröblacher, Simon last_name: Gröblacher - first_name: Jie full_name: Li, Jie last_name: Li citation: ama: Fan ZY, Qiu L, Gröblacher S, Li J. Microwave-optics entanglement via cavity optomagnomechanics. Laser and Photonics Reviews. 2023;17(12). doi:10.1002/lpor.202200866 apa: Fan, Z. Y., Qiu, L., Gröblacher, S., & Li, J. (2023). Microwave-optics entanglement via cavity optomagnomechanics. Laser and Photonics Reviews. Wiley. https://doi.org/10.1002/lpor.202200866 chicago: Fan, Zhi Yuan, Liu Qiu, Simon Gröblacher, and Jie Li. “Microwave-Optics Entanglement via Cavity Optomagnomechanics.” Laser and Photonics Reviews. Wiley, 2023. https://doi.org/10.1002/lpor.202200866. ieee: Z. Y. Fan, L. Qiu, S. Gröblacher, and J. Li, “Microwave-optics entanglement via cavity optomagnomechanics,” Laser and Photonics Reviews, vol. 17, no. 12. Wiley, 2023. ista: Fan ZY, Qiu L, Gröblacher S, Li J. 2023. Microwave-optics entanglement via cavity optomagnomechanics. Laser and Photonics Reviews. 17(12), 2200866. mla: Fan, Zhi Yuan, et al. “Microwave-Optics Entanglement via Cavity Optomagnomechanics.” Laser and Photonics Reviews, vol. 17, no. 12, 2200866, Wiley, 2023, doi:10.1002/lpor.202200866. short: Z.Y. Fan, L. Qiu, S. Gröblacher, J. Li, Laser and Photonics Reviews 17 (2023). date_created: 2023-11-05T23:00:54Z date_published: 2023-12-01T00:00:00Z date_updated: 2025-09-09T13:13:18Z day: '01' department: - _id: JoFi doi: 10.1002/lpor.202200866 external_id: arxiv: - '2208.10703' isi: - '001088860000001' intvolume: ' 17' isi: 1 issue: '12' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2208.10703 month: '12' oa: 1 oa_version: Preprint publication: Laser and Photonics Reviews publication_identifier: eissn: - 1863-8899 issn: - 1863-8880 publication_status: published publisher: Wiley quality_controlled: '1' scopus_import: '1' status: public title: Microwave-optics entanglement via cavity optomagnomechanics type: journal_article user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345 volume: 17 year: '2023' ... --- _id: '14517' abstract: - lang: eng text: 'State-of-the-art transmon qubits rely on large capacitors, which systematically improve their coherence due to reduced surface-loss participation. However, this approach increases both the footprint and the parasitic cross-coupling and is ultimately limited by radiation losses—a potential roadblock for scaling up quantum processors to millions of qubits. In this work we present transmon qubits with sizes as low as 36 × 39 µm2 with 100-nm-wide vacuum-gap capacitors that are micromachined from commercial silicon-on-insulator wafers and shadow evaporated with aluminum. We achieve a vacuum participation ratio up to 99.6% in an in-plane design that is compatible with standard coplanar circuits. Qubit relaxationtime measurements for small gaps with high zero-point electric field variance of up to 22 V/m reveal a double exponential decay indicating comparably strong qubit interaction with long-lived two-level systems. The exceptionally high selectivity of up to 20 dB to the superconductor-vacuum interface allows us to precisely back out the sub-single-photon dielectric loss tangent of aluminum oxide previously exposed to ambient conditions. In terms of future scaling potential, we achieve a ratio of qubit quality factor to a footprint area equal to 20 µm−2, which is comparable with the highest T1 devices relying on larger geometries, a value that could improve substantially for lower surface-loss superconductors. ' acknowledged_ssus: - _id: NanoFab acknowledgement: "This work was supported by the Austrian Science Fund (FWF) through BeyondC (F7105), the European Research Council under Grant Agreement No. 758053 (ERC StG QUNNECT) and a NOMIS foundation research grant. M.Z. was the recipient of a SAIA scholarship, E.R. of\r\na DOC fellowship of the Austrian Academy of Sciences, and M.P. of a Pöttinger scholarship at IST Austria. S.B. acknowledges support from Marie Skłodowska Curie Program No. 707438 (MSC-IF SUPEREOM). J.M.F. acknowledges support from the Horizon Europe Program HORIZON-CL4-2022-QUANTUM-01-SGA via Project No. 101113946 OpenSuperQPlus100 and the ISTA Nanofabrication Facility." article_number: '044054' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Martin full_name: Zemlicka, Martin id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87 last_name: Zemlicka orcid: 0009-0005-0878-3032 - first_name: Elena full_name: Redchenko, Elena id: 2C21D6E8-F248-11E8-B48F-1D18A9856A87 last_name: Redchenko - first_name: Matilda full_name: Peruzzo, Matilda id: 3F920B30-F248-11E8-B48F-1D18A9856A87 last_name: Peruzzo orcid: 0000-0002-3415-4628 - first_name: Farid full_name: Hassani, Farid id: 2AED110C-F248-11E8-B48F-1D18A9856A87 last_name: Hassani orcid: 0000-0001-6937-5773 - first_name: Andrea full_name: Trioni, Andrea id: 42F71B44-F248-11E8-B48F-1D18A9856A87 last_name: Trioni - first_name: Shabir full_name: Barzanjeh, Shabir id: 2D25E1F6-F248-11E8-B48F-1D18A9856A87 last_name: Barzanjeh orcid: 0000-0003-0415-1423 - 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: 'Zemlicka M, Redchenko E, Peruzzo M, et al. Compact vacuum-gap transmon qubits: Selective and sensitive probes for superconductor surface losses. Physical Review Applied. 2023;20(4). doi:10.1103/PhysRevApplied.20.044054' apa: 'Zemlicka, M., Redchenko, E., Peruzzo, M., Hassani, F., Trioni, A., Barzanjeh, S., & Fink, J. M. (2023). Compact vacuum-gap transmon qubits: Selective and sensitive probes for superconductor surface losses. Physical Review Applied. American Physical Society. https://doi.org/10.1103/PhysRevApplied.20.044054' chicago: 'Zemlicka, Martin, Elena Redchenko, Matilda Peruzzo, Farid Hassani, Andrea Trioni, Shabir Barzanjeh, and Johannes M Fink. “Compact Vacuum-Gap Transmon Qubits: Selective and Sensitive Probes for Superconductor Surface Losses.” Physical Review Applied. American Physical Society, 2023. https://doi.org/10.1103/PhysRevApplied.20.044054.' ieee: 'M. Zemlicka et al., “Compact vacuum-gap transmon qubits: Selective and sensitive probes for superconductor surface losses,” Physical Review Applied, vol. 20, no. 4. American Physical Society, 2023.' ista: 'Zemlicka M, Redchenko E, Peruzzo M, Hassani F, Trioni A, Barzanjeh S, Fink JM. 2023. Compact vacuum-gap transmon qubits: Selective and sensitive probes for superconductor surface losses. Physical Review Applied. 20(4), 044054.' mla: 'Zemlicka, Martin, et al. “Compact Vacuum-Gap Transmon Qubits: Selective and Sensitive Probes for Superconductor Surface Losses.” Physical Review Applied, vol. 20, no. 4, 044054, American Physical Society, 2023, doi:10.1103/PhysRevApplied.20.044054.' short: M. Zemlicka, E. Redchenko, M. Peruzzo, F. Hassani, A. Trioni, S. Barzanjeh, J.M. Fink, Physical Review Applied 20 (2023). corr_author: '1' date_created: 2023-11-12T23:00:55Z date_published: 2023-10-20T00:00:00Z date_updated: 2026-06-03T07:16:02Z day: '20' department: - _id: JoFi doi: 10.1103/PhysRevApplied.20.044054 ec_funded: 1 external_id: arxiv: - '2206.14104' isi: - '001095315600001' intvolume: ' 20' isi: 1 issue: '4' language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/2206.14104 month: '10' oa: 1 oa_version: Preprint project: - _id: 26336814-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '758053' name: A Fiber Optic Transceiver for Superconducting Qubits - _id: eb9b30ac-77a9-11ec-83b8-871f581d53d2 name: Protected states of quantum matter - _id: 258047B6-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '707438' name: 'Microwave-to-Optical Quantum Link: Quantum Teleportation and Quantum Illumination with cavity Optomechanics' - _id: bdb7cfc1-d553-11ed-ba76-d2eaab167738 grant_number: '101080139' name: Open Superconducting Quantum Computers (OpenSuperQPlus) - _id: bdb108fd-d553-11ed-ba76-83dc74a9864f grant_number: F07105 name: QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits publication: Physical Review Applied publication_identifier: eissn: - 2331-7019 publication_status: published publisher: American Physical Society quality_controlled: '1' related_material: record: - id: '14520' relation: research_data status: public scopus_import: '1' status: public title: 'Compact vacuum-gap transmon qubits: Selective and sensitive probes for superconductor surface losses' type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 20 year: '2023' ... --- _id: '14553' abstract: - lang: eng text: Quantum state tomography is an essential component of modern quantum technology. In application to continuous-variable harmonic-oscillator systems, such as the electromagnetic field, existing tomography methods typically reconstruct the state in discrete bases, and are hence limited to states with relatively low amplitudes and energies. Here, we overcome this limitation by utilizing a feed-forward neural network to obtain the density matrix directly in the continuous position basis. An important benefit of our approach is the ability to choose specific regions in the phase space for detailed reconstruction. This results in a relatively slow scaling of the amount of resources required for the reconstruction with the state amplitude, and hence allows us to dramatically increase the range of amplitudes accessible with our method. article_number: '042430' article_processing_charge: No article_type: original arxiv: 1 author: - first_name: Ekaterina full_name: Fedotova, Ekaterina id: c1bea5e1-878e-11ee-9dff-d7404e4422ab last_name: Fedotova orcid: 0000-0001-7242-015X - first_name: Nikolai full_name: Kuznetsov, Nikolai last_name: Kuznetsov - first_name: Egor full_name: Tiunov, Egor last_name: Tiunov - first_name: A. E. full_name: Ulanov, A. E. last_name: Ulanov - first_name: A. I. full_name: Lvovsky, A. I. last_name: Lvovsky citation: ama: Fedotova E, Kuznetsov N, Tiunov E, Ulanov AE, Lvovsky AI. Continuous-variable quantum tomography of high-amplitude states. Physical Review A. 2023;108(4). doi:10.1103/PhysRevA.108.042430 apa: Fedotova, E., Kuznetsov, N., Tiunov, E., Ulanov, A. E., & Lvovsky, A. I. (2023). Continuous-variable quantum tomography of high-amplitude states. Physical Review A. American Physical Society. https://doi.org/10.1103/PhysRevA.108.042430 chicago: Fedotova, Ekaterina, Nikolai Kuznetsov, Egor Tiunov, A. E. Ulanov, and A. I. Lvovsky. “Continuous-Variable Quantum Tomography of High-Amplitude States.” Physical Review A. American Physical Society, 2023. https://doi.org/10.1103/PhysRevA.108.042430. ieee: E. Fedotova, N. Kuznetsov, E. Tiunov, A. E. Ulanov, and A. I. Lvovsky, “Continuous-variable quantum tomography of high-amplitude states,” Physical Review A, vol. 108, no. 4. American Physical Society, 2023. ista: Fedotova E, Kuznetsov N, Tiunov E, Ulanov AE, Lvovsky AI. 2023. Continuous-variable quantum tomography of high-amplitude states. Physical Review A. 108(4), 042430. mla: Fedotova, Ekaterina, et al. “Continuous-Variable Quantum Tomography of High-Amplitude States.” Physical Review A, vol. 108, no. 4, 042430, American Physical Society, 2023, doi:10.1103/PhysRevA.108.042430. short: E. Fedotova, N. Kuznetsov, E. Tiunov, A.E. Ulanov, A.I. Lvovsky, Physical Review A 108 (2023). corr_author: '1' date_created: 2023-11-19T23:00:54Z date_published: 2023-10-30T00:00:00Z date_updated: 2024-10-09T21:07:19Z day: '30' department: - _id: JoFi doi: 10.1103/PhysRevA.108.042430 external_id: arxiv: - '2212.07406' intvolume: ' 108' issue: '4' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2212.07406 month: '10' oa: 1 oa_version: Preprint publication: Physical Review A publication_identifier: eissn: - 2469-9934 issn: - 2469-9926 publication_status: published publisher: American Physical Society quality_controlled: '1' scopus_import: '1' status: public title: Continuous-variable quantum tomography of high-amplitude states type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 108 year: '2023' ... --- _id: '14872' abstract: - lang: eng text: We entangled microwave and optical photons for the first time as verified by a measured two-mode vacuum squeezing of 0.7 dB. This electro-optic entanglement is the key resource needed to connect cryogenic quantum circuits. article_number: LM1F.3 article_processing_charge: No author: - first_name: Rishabh full_name: Sahu, Rishabh id: 47D26E34-F248-11E8-B48F-1D18A9856A87 last_name: Sahu orcid: 0000-0001-6264-2162 - first_name: Liu full_name: Qiu, Liu last_name: Qiu - first_name: William J full_name: Hease, William J id: 29705398-F248-11E8-B48F-1D18A9856A87 last_name: Hease orcid: 0000-0001-9868-2166 - 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: Yuri full_name: Minoguchi, Yuri last_name: Minoguchi - first_name: Peter full_name: Rabl, Peter last_name: Rabl - 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: 'Sahu R, Qiu L, Hease WJ, et al. Entangling microwaves and telecom wavelength light. In: Frontiers in Optics + Laser Science 2023. Optica Publishing Group; 2023. doi:10.1364/ls.2023.lm1f.3' apa: 'Sahu, R., Qiu, L., Hease, W. J., Arnold, G. M., Minoguchi, Y., Rabl, P., & Fink, J. M. (2023). Entangling microwaves and telecom wavelength light. In Frontiers in Optics + Laser Science 2023. Tacoma, WA, United States: Optica Publishing Group. https://doi.org/10.1364/ls.2023.lm1f.3' chicago: Sahu, Rishabh, Liu Qiu, William J Hease, Georg M Arnold, Yuri Minoguchi, Peter Rabl, and Johannes M Fink. “Entangling Microwaves and Telecom Wavelength Light.” In Frontiers in Optics + Laser Science 2023. Optica Publishing Group, 2023. https://doi.org/10.1364/ls.2023.lm1f.3. ieee: R. Sahu et al., “Entangling microwaves and telecom wavelength light,” in Frontiers in Optics + Laser Science 2023, Tacoma, WA, United States, 2023. ista: Sahu R, Qiu L, Hease WJ, Arnold GM, Minoguchi Y, Rabl P, Fink JM. 2023. Entangling microwaves and telecom wavelength light. Frontiers in Optics + Laser Science 2023. Laser Science, LM1F.3. mla: Sahu, Rishabh, et al. “Entangling Microwaves and Telecom Wavelength Light.” Frontiers in Optics + Laser Science 2023, LM1F.3, Optica Publishing Group, 2023, doi:10.1364/ls.2023.lm1f.3. short: R. Sahu, L. Qiu, W.J. Hease, G.M. Arnold, Y. Minoguchi, P. Rabl, J.M. Fink, in:, Frontiers in Optics + Laser Science 2023, Optica Publishing Group, 2023. conference: end_date: 2023-10-12 location: Tacoma, WA, United States name: Laser Science start_date: 2023-10-09 corr_author: '1' date_created: 2024-01-22T12:29:41Z date_published: 2023-10-01T00:00:00Z date_updated: 2024-10-09T21:07:59Z day: '01' department: - _id: JoFi doi: 10.1364/ls.2023.lm1f.3 language: - iso: eng month: '10' oa_version: None publication: Frontiers in Optics + Laser Science 2023 publication_identifier: isbn: - '9781957171296' publication_status: published publisher: Optica Publishing Group quality_controlled: '1' status: public title: Entangling microwaves and telecom wavelength light type: conference user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2023' ... --- _id: '14032' abstract: - lang: eng text: Arrays of Josephson junctions are governed by a competition between superconductivity and repulsive Coulomb interactions, and are expected to exhibit diverging low-temperature resistance when interactions exceed a critical level. Here we report a study of the transport and microwave response of Josephson arrays with interactions exceeding this level. Contrary to expectations, we observe that the array resistance drops dramatically as the temperature is decreased—reminiscent of superconducting behaviour—and then saturates at low temperature. Applying a magnetic field, we eventually observe a transition to a highly resistive regime. These observations can be understood within a theoretical picture that accounts for the effect of thermal fluctuations on the insulating phase. On the basis of the agreement between experiment and theory, we suggest that apparent superconductivity in our Josephson arrays arises from melting the zero-temperature insulator. acknowledged_ssus: - _id: M-Shop - _id: NanoFab acknowledgement: We thank D. Haviland, J. Pekola, C. Ciuti, A. Bubis and A. Shnirman for helpful feedback on the paper. This research was supported by the Scientific Service Units of IST Austria through resources provided by the MIBA Machine Shop and the Nanofabrication Facility. Work supported by the Austrian FWF grant P33692-N (S.M., J.S. and A.P.H.), the European Union’s Horizon 2020 Research and Innovation programme under the Marie Skłodowska-Curie Grant Agreement No. 754411 (J.S.) and a NOMIS foundation research grant (J.M.F. and A.P.H.). article_processing_charge: Yes (in subscription journal) article_type: original author: - first_name: Soham full_name: Mukhopadhyay, Soham id: FDE60288-A89D-11E9-947F-1AF6E5697425 last_name: Mukhopadhyay orcid: 0000-0001-5263-5559 - first_name: Jorden L full_name: Senior, Jorden L id: 5479D234-2D30-11EA-89CC-40953DDC885E last_name: Senior orcid: 0000-0002-0672-9295 - first_name: Jaime full_name: Saez Mollejo, Jaime id: e0390f72-f6e0-11ea-865d-862393336714 last_name: Saez Mollejo - first_name: Denise full_name: Puglia, Denise id: 4D495994-AE37-11E9-AC72-31CAE5697425 last_name: Puglia orcid: 0000-0003-1144-2763 - first_name: Martin full_name: Zemlicka, Martin id: 2DCF8DE6-F248-11E8-B48F-1D18A9856A87 last_name: Zemlicka orcid: 0009-0005-0878-3032 - first_name: Johannes M full_name: Fink, Johannes M id: 4B591CBA-F248-11E8-B48F-1D18A9856A87 last_name: Fink orcid: 0000-0001-8112-028X - first_name: Andrew P full_name: Higginbotham, Andrew P id: 4AD6785A-F248-11E8-B48F-1D18A9856A87 last_name: Higginbotham orcid: 0000-0003-2607-2363 citation: ama: Mukhopadhyay S, Senior JL, Saez Mollejo J, et al. Superconductivity from a melted insulator in Josephson junction arrays. Nature Physics. 2023;19:1630-1635. doi:10.1038/s41567-023-02161-w apa: Mukhopadhyay, S., Senior, J. L., Saez Mollejo, J., Puglia, D., Zemlicka, M., Fink, J. M., & Higginbotham, A. P. (2023). Superconductivity from a melted insulator in Josephson junction arrays. Nature Physics. Springer Nature. https://doi.org/10.1038/s41567-023-02161-w chicago: Mukhopadhyay, Soham, Jorden L Senior, Jaime Saez Mollejo, Denise Puglia, Martin Zemlicka, Johannes M Fink, and Andrew P Higginbotham. “Superconductivity from a Melted Insulator in Josephson Junction Arrays.” Nature Physics. Springer Nature, 2023. https://doi.org/10.1038/s41567-023-02161-w. ieee: S. Mukhopadhyay et al., “Superconductivity from a melted insulator in Josephson junction arrays,” Nature Physics, vol. 19. Springer Nature, pp. 1630–1635, 2023. ista: Mukhopadhyay S, Senior JL, Saez Mollejo J, Puglia D, Zemlicka M, Fink JM, Higginbotham AP. 2023. Superconductivity from a melted insulator in Josephson junction arrays. Nature Physics. 19, 1630–1635. mla: Mukhopadhyay, Soham, et al. “Superconductivity from a Melted Insulator in Josephson Junction Arrays.” Nature Physics, vol. 19, Springer Nature, 2023, pp. 1630–35, doi:10.1038/s41567-023-02161-w. short: S. Mukhopadhyay, J.L. Senior, J. Saez Mollejo, D. Puglia, M. Zemlicka, J.M. Fink, A.P. Higginbotham, Nature Physics 19 (2023) 1630–1635. corr_author: '1' date_created: 2023-08-11T07:41:17Z date_published: 2023-11-01T00:00:00Z date_updated: 2026-08-21T22:30:17Z day: '01' ddc: - '530' department: - _id: GradSch - _id: AnHi - _id: JoFi doi: 10.1038/s41567-023-02161-w ec_funded: 1 external_id: isi: - '001054563800006' file: - access_level: open_access checksum: 1fc86d71bfbf836e221c1e925343adc5 content_type: application/pdf creator: dernst date_created: 2024-01-29T11:25:38Z date_updated: 2024-01-29T11:25:38Z file_id: '14899' file_name: 2023_NaturePhysics_Mukhopadhyay.pdf file_size: 1977706 relation: main_file success: 1 file_date_updated: 2024-01-29T11:25:38Z has_accepted_license: '1' intvolume: ' 19' isi: 1 keyword: - General Physics and Astronomy language: - iso: eng month: '11' oa: 1 oa_version: Published Version page: 1630-1635 project: - _id: 0aa3608a-070f-11eb-9043-e9cd8a2bd931 grant_number: P33692 name: Cavity electromechanics across a quantum phase transition - _id: 260C2330-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '754411' name: ISTplus - Postdoctoral Fellowships - _id: eb9b30ac-77a9-11ec-83b8-871f581d53d2 name: Protected states of quantum matter publication: Nature Physics publication_identifier: eissn: - 1745-2481 issn: - 1745-2473 publication_status: published publisher: Springer Nature quality_controlled: '1' related_material: record: - id: '17881' relation: dissertation_contains status: public scopus_import: '1' status: public title: Superconductivity from a melted insulator in Josephson junction arrays 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: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 19 year: '2023' ... --- APC_amount: 6228 EUR DOAJ_listed: '1' OA_place: publisher OA_type: gold _id: '13200' abstract: - lang: eng text: Recent quantum technologies have established precise quantum control of various microscopic systems using electromagnetic waves. Interfaces based on cryogenic cavity electro-optic systems are particularly promising, due to the direct interaction between microwave and optical fields in the quantum regime. Quantum optical control of superconducting microwave circuits has been precluded so far due to the weak electro-optical coupling as well as quasi-particles induced by the pump laser. Here we report the coherent control of a superconducting microwave cavity using laser pulses in a multimode electro-optical device at millikelvin temperature with near-unity cooperativity. Both the stationary and instantaneous responses of the microwave and optical modes comply with the coherent electro-optical interaction, and reveal only minuscule amount of excess back-action with an unanticipated time delay. Our demonstration enables wide ranges of applications beyond quantum transductions, from squeezing and quantum non-demolition measurements of microwave fields, to entanglement generation and hybrid quantum networks. acknowledgement: This work was supported by the European Research Council under grant agreement no. 758053 (ERC StG QUNNECT), the European Union’s Horizon 2020 research and innovation program under grant agreement no. 899354 (FETopen SuperQuLAN), and the Austrian Science Fund (FWF) through BeyondC (F7105). L.Q. acknowledges generous support from the ISTFELLOW programme. W.H. is the recipient of an ISTplus postdoctoral fellowship with funding from the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement no. 754411. G.A. is the recipient of a DOC fellowship of the Austrian Academy of Sciences at IST Austria. article_number: '3784' article_processing_charge: Yes article_type: original arxiv: 1 author: - first_name: Liu full_name: Qiu, Liu id: 45e99c0d-1eb1-11eb-9b96-ed8ab2983cac last_name: Qiu orcid: 0000-0003-4345-4267 - first_name: Rishabh full_name: Sahu, Rishabh id: 47D26E34-F248-11E8-B48F-1D18A9856A87 last_name: Sahu orcid: 0000-0001-6264-2162 - first_name: William J full_name: Hease, William J id: 29705398-F248-11E8-B48F-1D18A9856A87 last_name: Hease orcid: 0000-0001-9868-2166 - 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: Johannes M full_name: Fink, Johannes M id: 4B591CBA-F248-11E8-B48F-1D18A9856A87 last_name: Fink orcid: 0000-0001-8112-028X citation: ama: Qiu L, Sahu R, Hease WJ, Arnold GM, Fink JM. Coherent optical control of a superconducting microwave cavity via electro-optical dynamical back-action. Nature Communications. 2023;14. doi:10.1038/s41467-023-39493-3 apa: Qiu, L., Sahu, R., Hease, W. J., Arnold, G. M., & Fink, J. M. (2023). Coherent optical control of a superconducting microwave cavity via electro-optical dynamical back-action. Nature Communications. Nature Research. https://doi.org/10.1038/s41467-023-39493-3 chicago: Qiu, Liu, Rishabh Sahu, William J Hease, Georg M Arnold, and Johannes M Fink. “Coherent Optical Control of a Superconducting Microwave Cavity via Electro-Optical Dynamical Back-Action.” Nature Communications. Nature Research, 2023. https://doi.org/10.1038/s41467-023-39493-3. ieee: L. Qiu, R. Sahu, W. J. Hease, G. M. Arnold, and J. M. Fink, “Coherent optical control of a superconducting microwave cavity via electro-optical dynamical back-action,” Nature Communications, vol. 14. Nature Research, 2023. ista: Qiu L, Sahu R, Hease WJ, Arnold GM, Fink JM. 2023. Coherent optical control of a superconducting microwave cavity via electro-optical dynamical back-action. Nature Communications. 14, 3784. mla: Qiu, Liu, et al. “Coherent Optical Control of a Superconducting Microwave Cavity via Electro-Optical Dynamical Back-Action.” Nature Communications, vol. 14, 3784, Nature Research, 2023, doi:10.1038/s41467-023-39493-3. short: L. Qiu, R. Sahu, W.J. Hease, G.M. Arnold, J.M. Fink, Nature Communications 14 (2023). corr_author: '1' date_created: 2023-07-09T22:01:11Z date_published: 2023-06-24T00:00:00Z date_updated: 2026-08-21T22:30:34Z day: '24' ddc: - '000' department: - _id: JoFi doi: 10.1038/s41467-023-39493-3 ec_funded: 1 external_id: arxiv: - '2210.12443' isi: - '001018100800002' pmid: - '37355691' file: - access_level: open_access checksum: ec7ccd2c08f90d59cab302fd0d7776a4 content_type: application/pdf creator: alisjak date_created: 2023-07-10T10:10:54Z date_updated: 2023-07-10T10:10:54Z file_id: '13206' file_name: 2023_NatureComms_Qiu.pdf file_size: 1349134 relation: main_file success: 1 file_date_updated: 2023-07-10T10:10:54Z has_accepted_license: '1' intvolume: ' 14' isi: 1 language: - iso: eng month: '06' oa: 1 oa_version: Published Version pmid: 1 project: - _id: 26336814-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '758053' name: A Fiber Optic Transceiver for Superconducting Qubits - _id: 9B868D20-BA93-11EA-9121-9846C619BF3A call_identifier: H2020 grant_number: '899354' name: Quantum Local Area Networks with Superconducting Qubits - _id: bdb108fd-d553-11ed-ba76-83dc74a9864f grant_number: F07105 name: QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits - _id: 260C2330-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '754411' name: ISTplus - Postdoctoral Fellowships - _id: 25681D80-B435-11E9-9278-68D0E5697425 call_identifier: FP7 grant_number: '291734' name: International IST Postdoc Fellowship Programme - _id: 2671EB66-B435-11E9-9278-68D0E5697425 name: Coherent on-chip conversion of superconducting qubit signals from microwaves to optical frequencies - _id: 3AC91DDA-15DF-11EA-824D-93A3E7B544D1 call_identifier: FWF name: FWF Open Access Fund publication: Nature Communications publication_identifier: eissn: - 2041-1723 publication_status: published publisher: Nature Research quality_controlled: '1' related_material: record: - id: '18871' relation: dissertation_contains status: public scopus_import: '1' status: public title: Coherent optical control of a superconducting microwave cavity via electro-optical dynamical back-action 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: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 14 year: '2023' ... --- OA_place: repository _id: '18953' abstract: - lang: eng text: The rapid development of superconducting quantum hardware is expected to run into significant I/O restrictions due to the need for large-scale error correction in a cryogenic environment. Classical data centers rely on fiber-optic interconnects to remove similar networking bottlenecks and to allow for reconfigurable, software-defined infrastructures. In the same spirit, ultra-cold electro-optic links have been proposed and used to generate qubit control signals, or to replace cryogenic readout electronics. So far, the latter suffered from either low efficiency, low bandwidth and the need for additional microwave drives, or breaking of Cooper pairs and qubit states. In this work we realize electro-optic microwave photonics at millikelvin temperatures to implement a radio-over-fiber qubit readout that does not require any active or passive cryogenic microwave equipment. We demonstrate all-optical single-shot-readout by means of the Jaynes-Cummings nonlinearity in a circulator-free readout scheme. Importantly, we do not observe any direct radiation impact on the qubit state as verified with high-fidelity quantum-non-demolition measurements despite the absence of shielding elements. This compatibility between superconducting circuits and telecom wavelength light is not only a prerequisite to establish modular quantum networks, it is also relevant for multiplexed readout of superconducting photon detectors and classical superconducting logic. Moreover, this experiment showcases the potential of electro-optic radiometry in harsh environments - an electronics-free sensing principle that extends into the THz regime with applications in radio astronomy, planetary missions and earth observation. acknowledgement: "We thank F. Hassani and M. Zemlicka for assistance\r\nwith qubit design and high power readout respectively,\r\nand P. Winkel and I. Pop at KIT for providing the JPA.\r\nThis work was supported by the European Research\r\nCouncil under grant agreement no. 758053 (ERC StG\r\nQUNNECT) and no. 101089099 (ERC CoG cQEO), the\r\nEuropean Union’s Horizon 2020 research and innovation\r\nprogram under grant agreement no. 899354 (FETopen\r\nSuperQuLAN) and the Austrian Science Fund (FWF)\r\nthrough BeyondC (grant no. F7105). L.Q. acknowledges\r\ngenerous support from the ISTFELLOW programme\r\nand G.A. is the recipient of a DOC fellowship of the\r\nAustrian Academy of Sciences at IST Austria." article_processing_charge: No arxiv: 1 author: - 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: Thomas full_name: Werner, Thomas id: 1fcd8497-dba3-11ea-a45e-c6fbd715f7c7 last_name: Werner orcid: 0009-0001-2346-5236 - first_name: Rishabh full_name: Sahu, Rishabh id: 47D26E34-F248-11E8-B48F-1D18A9856A87 last_name: Sahu orcid: 0000-0001-6264-2162 - first_name: Lucky full_name: Kapoor, Lucky id: 84b9700b-15b2-11ec-abd3-831089e67615 last_name: Kapoor orcid: 0000-0001-8319-2148 - first_name: Liu full_name: Qiu, Liu id: 45e99c0d-1eb1-11eb-9b96-ed8ab2983cac last_name: Qiu orcid: 0000-0003-4345-4267 - 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: Arnold GM, Werner T, Sahu R, Kapoor L, Qiu L, Fink JM. All-optical single-shot readout of a superconducting qubit. arXiv. doi:10.48550/ARXIV.2310.16817 apa: Arnold, G. M., Werner, T., Sahu, R., Kapoor, L., Qiu, L., & Fink, J. M. (n.d.). All-optical single-shot readout of a superconducting qubit. arXiv. https://doi.org/10.48550/ARXIV.2310.16817 chicago: Arnold, Georg M, Thomas Werner, Rishabh Sahu, Lucky Kapoor, Liu Qiu, and Johannes M Fink. “All-Optical Single-Shot Readout of a Superconducting Qubit.” ArXiv, n.d. https://doi.org/10.48550/ARXIV.2310.16817. ieee: G. M. Arnold, T. Werner, R. Sahu, L. Kapoor, L. Qiu, and J. M. Fink, “All-optical single-shot readout of a superconducting qubit,” arXiv. . ista: Arnold GM, Werner T, Sahu R, Kapoor L, Qiu L, Fink JM. All-optical single-shot readout of a superconducting qubit. arXiv, 10.48550/ARXIV.2310.16817. mla: Arnold, Georg M., et al. “All-Optical Single-Shot Readout of a Superconducting Qubit.” ArXiv, doi:10.48550/ARXIV.2310.16817. short: G.M. Arnold, T. Werner, R. Sahu, L. Kapoor, L. Qiu, J.M. Fink, ArXiv (n.d.). corr_author: '1' date_created: 2025-01-29T11:11:34Z date_published: 2023-10-25T00:00:00Z date_updated: 2026-08-21T22:30:34Z day: '25' department: - _id: JoFi doi: 10.48550/ARXIV.2310.16817 ec_funded: 1 external_id: arxiv: - '2310.16817' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.48550/arXiv.2310.16817 month: '10' oa: 1 oa_version: Preprint project: - _id: 26336814-B435-11E9-9278-68D0E5697425 call_identifier: H2020 grant_number: '758053' name: A Fiber Optic Transceiver for Superconducting Qubits - _id: bdadfa0d-d553-11ed-ba76-fb85edbd456a grant_number: '101089099' name: 'Cavity Quantum Electro Optics: Microwave photonics with nonclassical states' - _id: 9B868D20-BA93-11EA-9121-9846C619BF3A call_identifier: H2020 grant_number: '899354' name: Quantum Local Area Networks with Superconducting Qubits - _id: 2671EB66-B435-11E9-9278-68D0E5697425 name: Coherent on-chip conversion of superconducting qubit signals from microwaves to optical frequencies - _id: bdb108fd-d553-11ed-ba76-83dc74a9864f grant_number: F07105 name: QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits publication: arXiv publication_status: draft related_material: record: - id: '19073' relation: later_version status: public - id: '18871' relation: dissertation_contains status: public status: public title: All-optical single-shot readout of a superconducting qubit 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: 2DF688A6-F248-11E8-B48F-1D18A9856A87 year: '2023' ...