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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.","lang":"eng"}],"date_updated":"2025-07-15T09:17:40Z","citation":{"short":"R. Sahu, L. Qiu, W.J. Hease, G.M. Arnold, Y. Minoguchi, P. Rabl, J.M. Fink, Entangling Microwaves with Light, American Association for the Advancement of Science, 2023.","mla":"Sahu, Rishabh, et al. <i>Entangling Microwaves with Light</i>. Vol. 380, American Association for the Advancement of Science, 2023, pp. 718–21, doi:<a href=\"https://doi.org/10.1126/science.adg3812\">10.1126/science.adg3812</a>.","ista":"Sahu R, Qiu L, Hease WJ, Arnold GM, Minoguchi Y, Rabl P, Fink JM. 2023. Entangling microwaves with light. American Association for the Advancement of Science.","ama":"Sahu R, Qiu L, Hease WJ, et al. Entangling microwaves with light. 2023;380:718-721. doi:<a href=\"https://doi.org/10.1126/science.adg3812\">10.1126/science.adg3812</a>","apa":"Sahu, R., Qiu, L., Hease, W. J., Arnold, G. M., Minoguchi, Y., Rabl, P., &#38; Fink, J. M. (2023). <i>Entangling microwaves with light</i>. American Association for the Advancement of Science. <a href=\"https://doi.org/10.1126/science.adg3812\">https://doi.org/10.1126/science.adg3812</a>","ieee":"R. Sahu <i>et al.</i>, “Entangling microwaves with light,” American Association for the Advancement of Science, 2023.","chicago":"Sahu, Rishabh, Liu Qiu, William J Hease, Georg M Arnold, Y. Minoguchi, P. Rabl, and Johannes M Fink. “Entangling Microwaves with Light.” American Association for the Advancement of Science, 2023. <a href=\"https://doi.org/10.1126/science.adg3812\">https://doi.org/10.1126/science.adg3812</a>."},"year":"2023","isi":1,"external_id":{"arxiv":["2301.03315"],"isi":["000996515200004"]},"volume":380,"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).","publication_status":"published","date_created":"2023-05-31T11:39:24Z","department":[{"_id":"JoFi"}],"article_processing_charge":"No","title":"Entangling microwaves with light","intvolume":"       380","_id":"13106","author":[{"orcid":"0000-0001-6264-2162","full_name":"Sahu, Rishabh","first_name":"Rishabh","last_name":"Sahu","id":"47D26E34-F248-11E8-B48F-1D18A9856A87"},{"orcid":"0000-0003-4345-4267","full_name":"Qiu, Liu","first_name":"Liu","last_name":"Qiu","id":"45e99c0d-1eb1-11eb-9b96-ed8ab2983cac"},{"id":"29705398-F248-11E8-B48F-1D18A9856A87","last_name":"Hease","first_name":"William J","full_name":"Hease, William J","orcid":"0000-0001-9868-2166"},{"orcid":"0000-0003-1397-7876","full_name":"Arnold, Georg M","first_name":"Georg M","last_name":"Arnold","id":"3770C838-F248-11E8-B48F-1D18A9856A87"},{"full_name":"Minoguchi, Y.","last_name":"Minoguchi","first_name":"Y."},{"full_name":"Rabl, P.","first_name":"P.","last_name":"Rabl"},{"orcid":"0000-0001-8112-028X","full_name":"Fink, Johannes M","first_name":"Johannes M","last_name":"Fink","id":"4B591CBA-F248-11E8-B48F-1D18A9856A87"}],"publisher":"American Association for the Advancement of Science","page":"718-721","ec_funded":1,"publication_identifier":{"eissn":["1095-9203"],"issn":["0036-8075"]},"oa":1,"date_published":"2023-05-18T00:00:00Z","type":"dissertation","main_file_link":[{"open_access":"1","url":"https://doi.org/10.48550/arXiv.2301.03315"}],"status":"public","related_material":{"record":[{"status":"public","relation":"research_data","id":"13122"}],"link":[{"relation":"press_release","description":"News on ISTA Website","url":"https://ista.ac.at/en/news/wiring-up-quantum-circuits-with-light/"}]},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","oa_version":"Preprint","project":[{"name":"A Fiber Optic Transceiver for Superconducting Qubits","grant_number":"758053","call_identifier":"H2020","_id":"26336814-B435-11E9-9278-68D0E5697425"},{"name":"Quantum Local Area Networks with Superconducting Qubits","grant_number":"899354","call_identifier":"H2020","_id":"9B868D20-BA93-11EA-9121-9846C619BF3A"},{"name":"ISTplus - 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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. ","lang":"eng"}],"day":"05","degree_awarded":"PhD","doi":"10.15479/at:ista:13175","year":"2023","citation":{"mla":"Sahu, Rishabh. <i>Cavity Quantum Electrooptics</i>. Institute of Science and Technology Austria, 2023, doi:<a href=\"https://doi.org/10.15479/at:ista:13175\">10.15479/at:ista:13175</a>.","short":"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.","apa":"Sahu, R. (2023). <i>Cavity quantum electrooptics</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/at:ista:13175\">https://doi.org/10.15479/at:ista:13175</a>","ama":"Sahu R. Cavity quantum electrooptics. 2023. doi:<a href=\"https://doi.org/10.15479/at:ista:13175\">10.15479/at:ista:13175</a>","ieee":"R. Sahu, “Cavity quantum electrooptics,” Institute of Science and Technology Austria, 2023.","chicago":"Sahu, Rishabh. “Cavity Quantum Electrooptics.” Institute of Science and Technology Austria, 2023. <a href=\"https://doi.org/10.15479/at:ista:13175\">https://doi.org/10.15479/at:ista:13175</a>."},"date_updated":"2024-10-29T09:11:06Z","ddc":["537","535","539"],"title":"Cavity quantum electrooptics","alternative_title":["ISTA Thesis"],"department":[{"_id":"GradSch"},{"_id":"JoFi"}],"date_created":"2023-06-30T08:07:43Z","article_processing_charge":"No","publication_status":"published","author":[{"last_name":"Sahu","first_name":"Rishabh","full_name":"Sahu, Rishabh","orcid":"0000-0001-6264-2162","id":"47D26E34-F248-11E8-B48F-1D18A9856A87"}],"_id":"13175","publisher":"Institute of Science and Technology Austria","file_date_updated":"2023-07-06T11:35:15Z","ec_funded":1,"page":"202"},{"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.","volume":14,"ddc":["000"],"day":"24","arxiv":1,"doi":"10.1038/s41467-023-39493-3","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."}],"citation":{"apa":"Qiu, L., Sahu, R., Hease, W. J., Arnold, G. M., &#38; Fink, J. M. (2023). Coherent optical control of a superconducting microwave cavity via electro-optical dynamical back-action. <i>Nature Communications</i>. Nature Research. <a href=\"https://doi.org/10.1038/s41467-023-39493-3\">https://doi.org/10.1038/s41467-023-39493-3</a>","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. <i>Nature Communications</i>. 2023;14. doi:<a href=\"https://doi.org/10.1038/s41467-023-39493-3\">10.1038/s41467-023-39493-3</a>","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,” <i>Nature Communications</i>, vol. 14. Nature Research, 2023.","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.” <i>Nature Communications</i>. Nature Research, 2023. <a href=\"https://doi.org/10.1038/s41467-023-39493-3\">https://doi.org/10.1038/s41467-023-39493-3</a>.","short":"L. Qiu, R. Sahu, W.J. Hease, G.M. Arnold, J.M. Fink, Nature Communications 14 (2023).","mla":"Qiu, Liu, et al. “Coherent Optical Control of a Superconducting Microwave Cavity via Electro-Optical Dynamical Back-Action.” <i>Nature Communications</i>, vol. 14, 3784, Nature Research, 2023, doi:<a href=\"https://doi.org/10.1038/s41467-023-39493-3\">10.1038/s41467-023-39493-3</a>.","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."},"year":"2023","date_updated":"2024-08-07T07:11:55Z","external_id":{"isi":["001018100800002"],"pmid":["37355691"],"arxiv":["2210.12443"]},"isi":1,"publisher":"Nature Research","article_type":"original","ec_funded":1,"quality_controlled":"1","file_date_updated":"2023-07-10T10:10:54Z","article_processing_charge":"No","department":[{"_id":"JoFi"}],"date_created":"2023-07-09T22:01:11Z","publication_status":"published","intvolume":"        14","title":"Coherent optical control of a superconducting microwave cavity via electro-optical dynamical back-action","scopus_import":"1","pmid":1,"_id":"13200","author":[{"id":"45e99c0d-1eb1-11eb-9b96-ed8ab2983cac","orcid":"0000-0003-4345-4267","full_name":"Qiu, Liu","first_name":"Liu","last_name":"Qiu"},{"orcid":"0000-0001-6264-2162","full_name":"Sahu, Rishabh","first_name":"Rishabh","last_name":"Sahu","id":"47D26E34-F248-11E8-B48F-1D18A9856A87"},{"orcid":"0000-0001-9868-2166","full_name":"Hease, William J","first_name":"William J","last_name":"Hease","id":"29705398-F248-11E8-B48F-1D18A9856A87"},{"full_name":"Arnold, Georg M","orcid":"0000-0003-1397-7876","last_name":"Arnold","first_name":"Georg M","id":"3770C838-F248-11E8-B48F-1D18A9856A87"},{"first_name":"Johannes M","last_name":"Fink","orcid":"0000-0001-8112-028X","full_name":"Fink, Johannes M","id":"4B591CBA-F248-11E8-B48F-1D18A9856A87"}],"file":[{"access_level":"open_access","relation":"main_file","success":1,"creator":"alisjak","file_id":"13206","file_size":1349134,"checksum":"ec7ccd2c08f90d59cab302fd0d7776a4","date_created":"2023-07-10T10:10:54Z","file_name":"2023_NatureComms_Qiu.pdf","content_type":"application/pdf","date_updated":"2023-07-10T10:10:54Z"}],"status":"public","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publication_identifier":{"eissn":["2041-1723"]},"oa":1,"tmp":{"legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"type":"journal_article","date_published":"2023-06-24T00:00:00Z","language":[{"iso":"eng"}],"project":[{"grant_number":"758053","name":"A Fiber Optic Transceiver for Superconducting Qubits","_id":"26336814-B435-11E9-9278-68D0E5697425","call_identifier":"H2020"},{"name":"Quantum Local Area Networks with Superconducting Qubits","grant_number":"899354","_id":"9B868D20-BA93-11EA-9121-9846C619BF3A","call_identifier":"H2020"},{"name":"QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits","_id":"bdb108fd-d553-11ed-ba76-83dc74a9864f"},{"call_identifier":"H2020","_id":"260C2330-B435-11E9-9278-68D0E5697425","grant_number":"754411","name":"ISTplus - Postdoctoral Fellowships"},{"grant_number":"291734","name":"International IST Postdoc Fellowship Programme","call_identifier":"FP7","_id":"25681D80-B435-11E9-9278-68D0E5697425"},{"_id":"2671EB66-B435-11E9-9278-68D0E5697425","name":"Coherent on-chip conversion of superconducting qubit signals from microwaves to optical frequencies"}],"oa_version":"Published Version","article_number":"3784","month":"06","has_accepted_license":"1","publication":"Nature Communications"},{"publisher":"Institute of Science and Technology Austria","file_date_updated":"2023-07-06T11:37:40Z","ec_funded":1,"page":"190","alternative_title":["ISTA Thesis"],"title":"Cavity quantum electrooptics","department":[{"_id":"GradSch"},{"_id":"JoFi"}],"article_processing_charge":"No","date_created":"2023-05-05T11:08:50Z","publication_status":"published","author":[{"id":"47D26E34-F248-11E8-B48F-1D18A9856A87","first_name":"Rishabh","last_name":"Sahu","orcid":"0000-0001-6264-2162","full_name":"Sahu, Rishabh"}],"_id":"12900","ddc":["537","535","539"],"abstract":[{"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. ","lang":"eng"}],"day":"05","doi":"10.15479/at:ista:12900","degree_awarded":"PhD","year":"2023","citation":{"apa":"Sahu, R. (2023). <i>Cavity quantum electrooptics</i>. Institute of Science and Technology Austria. <a href=\"https://doi.org/10.15479/at:ista:12900\">https://doi.org/10.15479/at:ista:12900</a>","ama":"Sahu R. Cavity quantum electrooptics. 2023. doi:<a href=\"https://doi.org/10.15479/at:ista:12900\">10.15479/at:ista:12900</a>","ieee":"R. Sahu, “Cavity quantum electrooptics,” Institute of Science and Technology Austria, 2023.","chicago":"Sahu, Rishabh. “Cavity Quantum Electrooptics.” Institute of Science and Technology Austria, 2023. <a href=\"https://doi.org/10.15479/at:ista:12900\">https://doi.org/10.15479/at:ista:12900</a>.","mla":"Sahu, Rishabh. <i>Cavity Quantum Electrooptics</i>. Institute of Science and Technology Austria, 2023, doi:<a href=\"https://doi.org/10.15479/at:ista:12900\">10.15479/at:ista:12900</a>.","short":"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."},"date_updated":"2024-10-29T09:11:05Z","keyword":["quantum optics","electrooptics","quantum networks","quantum communication","transduction"],"language":[{"iso":"eng"}],"month":"05","project":[{"call_identifier":"H2020","_id":"26336814-B435-11E9-9278-68D0E5697425","name":"A Fiber Optic Transceiver for Superconducting Qubits","grant_number":"758053"},{"call_identifier":"H2020","_id":"9B868D20-BA93-11EA-9121-9846C619BF3A","grant_number":"899354","name":"Quantum Local Area Networks with Superconducting Qubits"},{"name":"QUANTUM INFORMATION SYSTEMS BEYOND CLASSICAL CAPABILITIES / P5- Integration of Superconducting Quantum Circuits","_id":"bdb108fd-d553-11ed-ba76-83dc74a9864f"}],"oa_version":"Published Version","acknowledged_ssus":[{"_id":"M-Shop"},{"_id":"SSU"},{"_id":"NanoFab"}],"has_accepted_license":"1","user_id":"8b945eb4-e2f2-11eb-945a-df72226e66a9","related_material":{"record":[{"id":"9114","relation":"part_of_dissertation","status":"public"},{"id":"10924","relation":"part_of_dissertation","status":"public"},{"relation":"new_edition","id":"13175","status":"public"}]},"status":"public","file":[{"creator":"rsahu","file_id":"12928","relation":"source_file","access_level":"closed","file_name":"thesis.zip","content_type":"application/x-zip-compressed","date_updated":"2023-06-06T22:30:03Z","embargo_to":"open_access","file_size":36767177,"checksum":"8cbdab9c37ee55e591092a6f66b272c4","date_created":"2023-05-09T08:45:14Z"},{"date_updated":"2023-07-06T11:37:40Z","file_name":"thesis_pdfa_final.pdf","content_type":"application/pdf","date_created":"2023-05-09T08:51:17Z","checksum":"439659ead46618147309be39d9dd5a8c","file_size":17501990,"file_id":"12929","creator":"rsahu","access_level":"closed","relation":"main_file"}],"supervisor":[{"id":"4B591CBA-F248-11E8-B48F-1D18A9856A87","full_name":"Fink, Johannes M","orcid":"0000-0001-8112-028X","last_name":"Fink","first_name":"Johannes M"}],"publication_identifier":{"issn":["2663 - 337X"],"isbn":["978-3-99078-030-5"]},"type":"dissertation","date_published":"2023-05-05T00:00:00Z","tmp":{"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)","image":"/images/cc_by_nc_sa.png","short":"CC BY-NC-SA (4.0)"}},{"external_id":{"arxiv":["2107.08303"],"isi":["000767892300013"]},"isi":1,"citation":{"ista":"Sahu R, Hease WJ, Rueda Sanchez AR, Arnold GM, Qiu L, Fink JM. 2022. Quantum-enabled operation of a microwave-optical interface. Nature Communications. 13, 1276.","short":"R. Sahu, W.J. Hease, A.R. Rueda Sanchez, G.M. Arnold, L. Qiu, J.M. Fink, Nature Communications 13 (2022).","mla":"Sahu, Rishabh, et al. “Quantum-Enabled Operation of a Microwave-Optical Interface.” <i>Nature Communications</i>, vol. 13, 1276, Springer Nature, 2022, doi:<a href=\"https://doi.org/10.1038/s41467-022-28924-2\">10.1038/s41467-022-28924-2</a>.","chicago":"Sahu, Rishabh, William J Hease, Alfredo R Rueda Sanchez, Georg M Arnold, Liu Qiu, and Johannes M Fink. “Quantum-Enabled Operation of a Microwave-Optical Interface.” <i>Nature Communications</i>. Springer Nature, 2022. <a href=\"https://doi.org/10.1038/s41467-022-28924-2\">https://doi.org/10.1038/s41467-022-28924-2</a>.","ieee":"R. Sahu, W. J. Hease, A. R. Rueda Sanchez, G. M. Arnold, L. Qiu, and J. M. Fink, “Quantum-enabled operation of a microwave-optical interface,” <i>Nature Communications</i>, vol. 13. Springer Nature, 2022.","ama":"Sahu R, Hease WJ, Rueda Sanchez AR, Arnold GM, Qiu L, Fink JM. Quantum-enabled operation of a microwave-optical interface. <i>Nature Communications</i>. 2022;13. doi:<a href=\"https://doi.org/10.1038/s41467-022-28924-2\">10.1038/s41467-022-28924-2</a>","apa":"Sahu, R., Hease, W. J., Rueda Sanchez, A. R., Arnold, G. M., Qiu, L., &#38; Fink, J. M. (2022). Quantum-enabled operation of a microwave-optical interface. <i>Nature Communications</i>. Springer Nature. <a href=\"https://doi.org/10.1038/s41467-022-28924-2\">https://doi.org/10.1038/s41467-022-28924-2</a>"},"year":"2022","date_updated":"2024-10-29T09:11:06Z","abstract":[{"lang":"eng","text":"Solid-state microwave systems offer strong interactions for fast quantum logic and sensing but photons at telecom wavelength are the ideal choice for high-density low-loss quantum interconnects. A general-purpose interface that can make use of single photon effects requires < 1 input noise quanta, which has remained elusive due to either low efficiency or pump induced heating. Here we demonstrate coherent electro-optic modulation on nanosecond-timescales with only 0.16+0.02−0.01 microwave input noise photons with a total bidirectional transduction efficiency of 8.7% (or up to 15% with 0.41+0.02−0.02), as required for near-term heralded quantum network protocols. The use of short and high-power optical pump pulses also enables near-unity cooperativity of the electro-optic interaction leading to an internal pure conversion efficiency of up to 99.5%. Together with the low mode occupancy this provides evidence for electro-optic laser cooling and vacuum amplification as predicted a decade ago."}],"day":"11","doi":"10.1038/s41467-022-28924-2","arxiv":1,"ddc":["530"],"volume":13,"acknowledgement":"The authors thank S. Wald and F. Diorico for their help with optical filtering, O. Hosten\r\nand M. Aspelmeyer for equipment, H.G.L. Schwefel for materials and discussions, L.\r\nDrmic and P. Zielinski for software support, and the MIBA workshop at IST Austria for\r\nmachining the microwave cavity. This work was supported by the European Research\r\nCouncil under grant agreement no. 758053 (ERC StG QUNNECT) and the European\r\nUnion’s Horizon 2020 research and innovation program under grant agreement no.\r\n899354 (FETopen SuperQuLAN). W.H. is the recipient of an ISTplus postdoctoral fellowship\r\nwith funding from the European Union’s Horizon 2020 research and innovation\r\nprogram under the Marie Skłodowska-Curie grant agreement no. 754411. G.A. is the\r\nrecipient of a DOC fellowship of the Austrian Academy of Sciences at IST Austria. J.M.F.\r\nacknowledges support from the Austrian Science Fund (FWF) through BeyondC (F7105)\r\nand the European Union’s Horizon 2020 research and innovation programs under grant\r\nagreement no. 862644 (FETopen QUARTET).","author":[{"first_name":"Rishabh","last_name":"Sahu","orcid":"0000-0001-6264-2162","full_name":"Sahu, Rishabh","id":"47D26E34-F248-11E8-B48F-1D18A9856A87"},{"orcid":"0000-0001-9868-2166","full_name":"Hease, William J","first_name":"William J","last_name":"Hease","id":"29705398-F248-11E8-B48F-1D18A9856A87"},{"orcid":"0000-0001-6249-5860","full_name":"Rueda Sanchez, Alfredo R","first_name":"Alfredo R","last_name":"Rueda Sanchez","id":"3B82B0F8-F248-11E8-B48F-1D18A9856A87"},{"id":"3770C838-F248-11E8-B48F-1D18A9856A87","last_name":"Arnold","first_name":"Georg M","full_name":"Arnold, Georg M","orcid":"0000-0003-1397-7876"},{"orcid":"0000-0003-4345-4267","full_name":"Qiu, Liu","first_name":"Liu","last_name":"Qiu","id":"45e99c0d-1eb1-11eb-9b96-ed8ab2983cac"},{"id":"4B591CBA-F248-11E8-B48F-1D18A9856A87","last_name":"Fink","first_name":"Johannes M","full_name":"Fink, Johannes M","orcid":"0000-0001-8112-028X"}],"scopus_import":"1","_id":"10924","intvolume":"        13","title":"Quantum-enabled operation of a microwave-optical interface","department":[{"_id":"JoFi"}],"article_processing_charge":"No","date_created":"2022-03-27T22:01:45Z","publication_status":"published","file_date_updated":"2022-03-28T08:02:12Z","ec_funded":1,"quality_controlled":"1","article_type":"original","publisher":"Springer Nature","type":"journal_article","date_published":"2022-03-11T00:00:00Z","tmp":{"legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"oa":1,"publication_identifier":{"eissn":["20411723"]},"status":"public","related_material":{"record":[{"id":"12900","relation":"dissertation_contains","status":"public"},{"relation":"dissertation_contains","id":"13175","status":"public"}]},"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","file":[{"success":1,"access_level":"open_access","relation":"main_file","file_id":"10929","creator":"dernst","date_created":"2022-03-28T08:02:12Z","file_size":1167492,"checksum":"7c5176db7b8e2ed18a4e0c5aca70a72c","date_updated":"2022-03-28T08:02:12Z","content_type":"application/pdf","file_name":"2022_NatureCommunications_Sahu.pdf"}],"has_accepted_license":"1","publication":"Nature Communications","article_number":"1276","month":"03","project":[{"call_identifier":"H2020","_id":"26336814-B435-11E9-9278-68D0E5697425","name":"A Fiber Optic Transceiver for Superconducting Qubits","grant_number":"758053"},{"grant_number":"899354","name":"Quantum Local Area Networks with Superconducting Qubits","_id":"9B868D20-BA93-11EA-9121-9846C619BF3A","call_identifier":"H2020"},{"name":"ISTplus - Postdoctoral Fellowships","grant_number":"754411","_id":"260C2330-B435-11E9-9278-68D0E5697425","call_identifier":"H2020"},{"call_identifier":"FWF","_id":"26927A52-B435-11E9-9278-68D0E5697425","name":"Integrating superconducting quantum circuits","grant_number":"F07105"},{"call_identifier":"H2020","_id":"237CBA6C-32DE-11EA-91FC-C7463DDC885E","grant_number":"862644","name":"Quantum readout techniques and technologies"}],"oa_version":"Published Version","acknowledged_ssus":[{"_id":"M-Shop"}],"language":[{"iso":"eng"}]},{"abstract":[{"text":"We investigate the deterministic generation and distribution of entanglement in large quantum networks by driving distant qubits with the output fields of a nondegenerate parametric amplifier. In this setting, the amplifier produces a continuous Gaussian two-mode squeezed state, which acts as a quantum-correlated reservoir for the qubits and relaxes them into a highly entangled steady state. Here we are interested in the maximal amount of entanglement and the optimal entanglement generation rates that can be achieved with this scheme under realistic conditions taking, in particular, the finite amplifier bandwidth, waveguide losses, and propagation delays into account. By combining exact numerical simulations of the full network with approximate analytic results, we predict the optimal working point for the amplifier and the corresponding qubit-qubit entanglement under various conditions. Our findings show that this passive conversion of Gaussian into discrete-variable entanglement offers a robust and experimentally very attractive approach for operating large optical, microwave, or hybrid quantum networks, for which efficient parametric amplifiers are currently developed.","lang":"eng"}],"arxiv":1,"doi":"10.1103/PhysRevA.105.062454","day":"29","isi":1,"external_id":{"isi":["000824330200003"],"arxiv":["2204.02993"]},"date_updated":"2023-08-03T11:58:16Z","citation":{"apa":"Agustí, J., Minoguchi, Y., Fink, J. M., &#38; Rabl, P. (2022). Long-distance distribution of qubit-qubit entanglement using Gaussian-correlated photonic beams. <i>Physical Review A</i>. American Physical Society. <a href=\"https://doi.org/10.1103/PhysRevA.105.062454\">https://doi.org/10.1103/PhysRevA.105.062454</a>","ama":"Agustí J, Minoguchi Y, Fink JM, Rabl P. Long-distance distribution of qubit-qubit entanglement using Gaussian-correlated photonic beams. <i>Physical Review A</i>. 2022;105(6). doi:<a href=\"https://doi.org/10.1103/PhysRevA.105.062454\">10.1103/PhysRevA.105.062454</a>","chicago":"Agustí, J., Y. Minoguchi, Johannes M Fink, and P. Rabl. “Long-Distance Distribution of Qubit-Qubit Entanglement Using Gaussian-Correlated Photonic Beams.” <i>Physical Review A</i>. American Physical Society, 2022. <a href=\"https://doi.org/10.1103/PhysRevA.105.062454\">https://doi.org/10.1103/PhysRevA.105.062454</a>.","ieee":"J. Agustí, Y. Minoguchi, J. M. Fink, and P. Rabl, “Long-distance distribution of qubit-qubit entanglement using Gaussian-correlated photonic beams,” <i>Physical Review A</i>, vol. 105, no. 6. American Physical Society, 2022.","mla":"Agustí, J., et al. “Long-Distance Distribution of Qubit-Qubit Entanglement Using Gaussian-Correlated Photonic Beams.” <i>Physical Review A</i>, vol. 105, no. 6, 062454, American Physical Society, 2022, doi:<a href=\"https://doi.org/10.1103/PhysRevA.105.062454\">10.1103/PhysRevA.105.062454</a>.","short":"J. Agustí, Y. Minoguchi, J.M. Fink, P. Rabl, Physical Review A 105 (2022).","ista":"Agustí J, Minoguchi Y, Fink JM, Rabl P. 2022. Long-distance distribution of qubit-qubit entanglement using Gaussian-correlated photonic beams. Physical Review A. 105(6), 062454."},"year":"2022","acknowledgement":"We thank T. Mavrogordatos and D. Zhu for initial contribution on the presented topic and K. Fedorov for stimulating discussions on entangled microwave beams. This work was supported by the Austrian Science Fund (FWF) through Grant No. P32299 (PHONED) and the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 899354 (SuperQuLAN). Most of the computational results presented were obtained using the CLIP cluster [65].","volume":105,"title":"Long-distance distribution of qubit-qubit entanglement using Gaussian-correlated photonic beams","intvolume":"       105","publication_status":"published","department":[{"_id":"JoFi"}],"article_processing_charge":"No","date_created":"2022-07-17T22:01:55Z","author":[{"first_name":"J.","last_name":"Agustí","full_name":"Agustí, J."},{"full_name":"Minoguchi, Y.","last_name":"Minoguchi","first_name":"Y."},{"id":"4B591CBA-F248-11E8-B48F-1D18A9856A87","last_name":"Fink","first_name":"Johannes M","full_name":"Fink, Johannes M","orcid":"0000-0001-8112-028X"},{"last_name":"Rabl","first_name":"P.","full_name":"Rabl, P."}],"issue":"6","_id":"11591","scopus_import":"1","article_type":"original","publisher":"American Physical Society","quality_controlled":"1","ec_funded":1,"oa":1,"publication_identifier":{"eissn":["2469-9934"],"issn":["2469-9926"]},"date_published":"2022-06-29T00:00:00Z","type":"journal_article","user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","status":"public","main_file_link":[{"open_access":"1","url":" https://doi.org/10.48550/arXiv.2204.02993"}],"month":"06","article_number":"062454","oa_version":"Preprint","project":[{"_id":"9B868D20-BA93-11EA-9121-9846C619BF3A","call_identifier":"H2020","grant_number":"899354","name":"Quantum Local Area Networks with Superconducting Qubits"}],"publication":"Physical Review A","language":[{"iso":"eng"}]},{"publication":"PRX Quantum","has_accepted_license":"1","acknowledged_ssus":[{"_id":"M-Shop"}],"oa_version":"Published Version","project":[{"call_identifier":"H2020","_id":"26336814-B435-11E9-9278-68D0E5697425","name":"A Fiber Optic Transceiver for Superconducting Qubits","grant_number":"758053"},{"call_identifier":"H2020","_id":"260C2330-B435-11E9-9278-68D0E5697425","name":"ISTplus - Postdoctoral Fellowships","grant_number":"754411"},{"name":"Quantum Local Area Networks with Superconducting Qubits","grant_number":"899354","call_identifier":"H2020","_id":"9B868D20-BA93-11EA-9121-9846C619BF3A"},{"name":"Integrating superconducting quantum circuits","grant_number":"F07105","call_identifier":"FWF","_id":"26927A52-B435-11E9-9278-68D0E5697425"},{"name":"Coherent on-chip conversion of superconducting qubit signals from microwaves to optical frequencies","_id":"2671EB66-B435-11E9-9278-68D0E5697425"}],"month":"11","article_number":"020315","language":[{"iso":"eng"}],"tmp":{"legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"date_published":"2020-11-23T00:00:00Z","type":"journal_article","publication_identifier":{"issn":["2691-3399"]},"oa":1,"file":[{"relation":"main_file","success":1,"access_level":"open_access","creator":"dernst","file_id":"9115","file_size":2146924,"checksum":"b70b12ded6d7660d4c9037eb09bfed0c","date_created":"2021-02-12T11:16:16Z","content_type":"application/pdf","file_name":"2020_PRXQuantum_Hease.pdf","date_updated":"2021-02-12T11:16:16Z"}],"user_id":"4359f0d1-fa6c-11eb-b949-802e58b17ae8","status":"public","related_material":{"link":[{"url":"https://ist.ac.at/en/news/how-to-transport-microwave-quantum-information-via-optical-fiber/","description":"News on IST Homepage","relation":"press_release"}],"record":[{"relation":"research_data","id":"13071","status":"public"},{"status":"public","relation":"dissertation_contains","id":"12900"},{"relation":"dissertation_contains","id":"13175","status":"public"}]},"_id":"9114","author":[{"first_name":"William J","last_name":"Hease","orcid":"0000-0001-9868-2166","full_name":"Hease, William J","id":"29705398-F248-11E8-B48F-1D18A9856A87"},{"orcid":"0000-0001-6249-5860","full_name":"Rueda Sanchez, Alfredo R","first_name":"Alfredo R","last_name":"Rueda Sanchez","id":"3B82B0F8-F248-11E8-B48F-1D18A9856A87"},{"first_name":"Rishabh","last_name":"Sahu","orcid":"0000-0001-6264-2162","full_name":"Sahu, Rishabh","id":"47D26E34-F248-11E8-B48F-1D18A9856A87"},{"id":"45598606-F248-11E8-B48F-1D18A9856A87","last_name":"Wulf","first_name":"Matthias","full_name":"Wulf, Matthias","orcid":"0000-0001-6613-1378"},{"last_name":"Arnold","first_name":"Georg M","full_name":"Arnold, Georg M","orcid":"0000-0003-1397-7876","id":"3770C838-F248-11E8-B48F-1D18A9856A87"},{"first_name":"Harald G.L.","last_name":"Schwefel","full_name":"Schwefel, Harald G.L."},{"orcid":"0000-0001-8112-028X","full_name":"Fink, Johannes M","first_name":"Johannes M","last_name":"Fink","id":"4B591CBA-F248-11E8-B48F-1D18A9856A87"}],"issue":"2","publication_status":"published","date_created":"2021-02-12T10:41:28Z","department":[{"_id":"JoFi"}],"article_processing_charge":"No","title":"Bidirectional electro-optic wavelength conversion in the quantum ground state","intvolume":"         1","ec_funded":1,"quality_controlled":"1","file_date_updated":"2021-02-12T11:16:16Z","publisher":"American Physical Society","article_type":"original","date_updated":"2024-10-29T09:11:05Z","citation":{"apa":"Hease, W. J., Rueda Sanchez, A. R., Sahu, R., Wulf, M., Arnold, G. M., Schwefel, H. G. L., &#38; Fink, J. M. (2020). Bidirectional electro-optic wavelength conversion in the quantum ground state. <i>PRX Quantum</i>. American Physical Society. <a href=\"https://doi.org/10.1103/prxquantum.1.020315\">https://doi.org/10.1103/prxquantum.1.020315</a>","ama":"Hease WJ, Rueda Sanchez AR, Sahu R, et al. Bidirectional electro-optic wavelength conversion in the quantum ground state. <i>PRX Quantum</i>. 2020;1(2). doi:<a href=\"https://doi.org/10.1103/prxquantum.1.020315\">10.1103/prxquantum.1.020315</a>","ieee":"W. J. Hease <i>et al.</i>, “Bidirectional electro-optic wavelength conversion in the quantum ground state,” <i>PRX Quantum</i>, vol. 1, no. 2. American Physical Society, 2020.","chicago":"Hease, William J, Alfredo R Rueda Sanchez, Rishabh Sahu, Matthias Wulf, Georg M Arnold, Harald G.L. Schwefel, and Johannes M Fink. “Bidirectional Electro-Optic Wavelength Conversion in the Quantum Ground State.” <i>PRX Quantum</i>. American Physical Society, 2020. <a href=\"https://doi.org/10.1103/prxquantum.1.020315\">https://doi.org/10.1103/prxquantum.1.020315</a>.","short":"W.J. Hease, A.R. Rueda Sanchez, R. Sahu, M. Wulf, G.M. Arnold, H.G.L. Schwefel, J.M. Fink, PRX Quantum 1 (2020).","mla":"Hease, William J., et al. “Bidirectional Electro-Optic Wavelength Conversion in the Quantum Ground State.” <i>PRX Quantum</i>, vol. 1, no. 2, 020315, American Physical Society, 2020, doi:<a href=\"https://doi.org/10.1103/prxquantum.1.020315\">10.1103/prxquantum.1.020315</a>.","ista":"Hease WJ, Rueda Sanchez AR, Sahu R, Wulf M, Arnold GM, Schwefel HGL, Fink JM. 2020. Bidirectional electro-optic wavelength conversion in the quantum ground state. PRX Quantum. 1(2), 020315."},"year":"2020","isi":1,"external_id":{"isi":["000674680100001"]},"doi":"10.1103/prxquantum.1.020315","day":"23","abstract":[{"text":"Microwave photonics lends the advantages of fiber optics to electronic sensing and communication systems. In contrast to nonlinear optics, electro-optic devices so far require classical modulation fields whose variance is dominated by electronic or thermal noise rather than quantum fluctuations. Here we demonstrate bidirectional single-sideband conversion of X band microwave to C band telecom light with a microwave mode occupancy as low as 0.025 ± 0.005 and an added output noise of less than or equal to 0.074 photons. This is facilitated by radiative cooling and a triply resonant ultra-low-loss transducer operating at millikelvin temperatures. The high bandwidth of 10.7 MHz and total (internal) photon conversion\r\nefficiency of 0.03% (0.67%) combined with the extremely slow heating rate of 1.1 added output noise photons per second for the highest available pump power of 1.48 mW puts near-unity efficiency pulsed quantum transduction within reach. Together with the non-Gaussian resources of superconducting qubits this might provide the practical foundation to extend the range and scope of current quantum networks in analogy to electrical repeaters in classical fiber optic communication.","lang":"eng"}],"volume":1,"acknowledgement":"The authors acknowledge the support of T. Menner, A. Arslani, and T. Asenov from the Miba machine shop for machining the microwave cavity, and thank S. Barzanjeh, F. Sedlmeir, and C. Marquardt for fruitful discussions. This work is supported by IST Austria and the European Research Council under Grant No. 758053 (ERC StG QUNNECT). 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 No. 754411.\r\nG.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 (F71) and the European Union’s Horizon 2020 research and innovation program under Grant No. 899354 (FET Open SuperQuLAN). H.G.L.S. acknowledges support from the Aotearoa/New Zealand’s MBIE Endeavour Smart Ideas Grant No UOOX1805.","ddc":["530"]}]