[{"citation":{"apa":"Lammers, J., Ares, L., Pegoraro, F., Held, P., Brecht, B., Sperling, J., &#38; Silberhorn, C. (2026). Resource-efficient universal photonic processors based on time-multiplexed hybrid architectures. <i>Physical Review Applied</i>, <i>25</i>(5), Article 054011. <a href=\"https://doi.org/10.1103/x99y-2sms\">https://doi.org/10.1103/x99y-2sms</a>","ieee":"J. Lammers <i>et al.</i>, “Resource-efficient universal photonic processors based on time-multiplexed hybrid architectures,” <i>Physical Review Applied</i>, vol. 25, no. 5, Art. no. 054011, 2026, doi: <a href=\"https://doi.org/10.1103/x99y-2sms\">10.1103/x99y-2sms</a>.","chicago":"Lammers, Jonas, Laura Ares, Federico Pegoraro, Philip Held, Benjamin Brecht, Jan Sperling, and Christine Silberhorn. “Resource-Efficient Universal Photonic Processors Based on Time-Multiplexed Hybrid Architectures.” <i>Physical Review Applied</i> 25, no. 5 (2026). <a href=\"https://doi.org/10.1103/x99y-2sms\">https://doi.org/10.1103/x99y-2sms</a>.","short":"J. Lammers, L. Ares, F. Pegoraro, P. Held, B. Brecht, J. Sperling, C. Silberhorn, Physical Review Applied 25 (2026).","mla":"Lammers, Jonas, et al. “Resource-Efficient Universal Photonic Processors Based on Time-Multiplexed Hybrid Architectures.” <i>Physical Review Applied</i>, vol. 25, no. 5, 054011, American Physical Society (APS), 2026, doi:<a href=\"https://doi.org/10.1103/x99y-2sms\">10.1103/x99y-2sms</a>.","ama":"Lammers J, Ares L, Pegoraro F, et al. Resource-efficient universal photonic processors based on time-multiplexed hybrid architectures. <i>Physical Review Applied</i>. 2026;25(5). doi:<a href=\"https://doi.org/10.1103/x99y-2sms\">10.1103/x99y-2sms</a>","bibtex":"@article{Lammers_Ares_Pegoraro_Held_Brecht_Sperling_Silberhorn_2026, title={Resource-efficient universal photonic processors based on time-multiplexed hybrid architectures}, volume={25}, DOI={<a href=\"https://doi.org/10.1103/x99y-2sms\">10.1103/x99y-2sms</a>}, number={5054011}, journal={Physical Review Applied}, publisher={American Physical Society (APS)}, author={Lammers, Jonas and Ares, Laura and Pegoraro, Federico and Held, Philip and Brecht, Benjamin and Sperling, Jan and Silberhorn, Christine}, year={2026} }"},"status":"public","user_id":"75127","volume":25,"_id":"65575","publisher":"American Physical Society (APS)","abstract":[{"lang":"eng","text":"<jats:p>For the ever-growing field of quantum information processing, large-scale, efficient multiport interferometers serving as photonic processors are required. In this context, the suitability of quantum walks as the interferometric base for universal computation has been theoretically proven. In this work, we bridge the gap between theoretical proposals and state-of-the-art experimental capabilities by providing the recipe for the implementation of a universal photonic processor in discrete-time quantum walks. Specifically, we present the protocol for translating arbitrary linear transformations into the coin and step operator of a quantum walk and map these to the experimental parameters of the established time-multiplexed platform [A. Schreiber , Phys. Rev. Lett. , 050502 (2010)]. We show that our interface is highly scalable and resource efficient due to the hybrid encoding consisting of multiple degrees of freedom. Finally, we prove that our system is highly resilient against experimental imperfections and show that it compares favorably against existing architectures.</jats:p>"}],"issue":"5","publication":"Physical Review Applied","type":"journal_article","department":[{"_id":"623"},{"_id":"15"},{"_id":"170"},{"_id":"706"},{"_id":"429"}],"date_created":"2026-05-07T07:00:08Z","publication_status":"published","date_updated":"2026-05-07T07:01:09Z","intvolume":"        25","year":"2026","title":"Resource-efficient universal photonic processors based on time-multiplexed hybrid architectures","author":[{"last_name":"Lammers","first_name":"Jonas","full_name":"Lammers, Jonas"},{"full_name":"Ares, Laura","first_name":"Laura","last_name":"Ares"},{"id":"88928","first_name":"Federico","last_name":"Pegoraro","full_name":"Pegoraro, Federico"},{"id":"68236","last_name":"Held","first_name":"Philip","full_name":"Held, Philip"},{"full_name":"Brecht, Benjamin","first_name":"Benjamin","orcid":"0000-0003-4140-0556 ","last_name":"Brecht","id":"27150"},{"full_name":"Sperling, Jan","first_name":"Jan","last_name":"Sperling","orcid":"0000-0002-5844-3205","id":"75127"},{"id":"26263","full_name":"Silberhorn, Christine","first_name":"Christine","last_name":"Silberhorn"}],"publication_identifier":{"issn":["2331-7019"]},"doi":"10.1103/x99y-2sms","article_number":"054011","language":[{"iso":"eng"}]},{"department":[{"_id":"288"},{"_id":"623"},{"_id":"15"}],"type":"journal_article","keyword":["Photonic Quantum Computing","Time-multiplexing","Quantum Information"],"date_created":"2026-07-01T07:47:15Z","related_material":{"link":[{"url":"https://static-content.springer.com/esm/art%3A10.1038%2Fs41467-026-74861-9/MediaObjects/41467_2026_74861_MOESM1_ESM.pdf","relation":"supplementary_material","description":"Supplementary notes to the main article"},{"url":"https://doi.org/10.5281/zenodo.20396394","relation":"supplementary_material","description":"Datasets and code"}]},"abstract":[{"lang":"eng","text":"The two-qubit controlled-not (C-NOT) gate is an essential component for gate-based quantum circuits. In fact, its operation, combined with single qubit rotations allows to realise any quantum circuit. Several strategies have been adopted in order to build quantum gates. Among them, photonics offers the dual advantage of excellent isolation from the environment and ease of manipulation at the single qubit level. Here we adopt a scalable time-multiplexed approach in order to build a fully reconfigurable architecture capable of implementing a post-selected C-NOT gate with a fidelity of (93.8 ± 1.4)%. We then show how our time-multiplexed platform can be employed to combine a C-NOT and a single qubit gate in order to generate the four Bell states."}],"publication":"Nature Communications","issue":"1","doi":"10.1038/s41467-026-74861-9","language":[{"iso":"eng"}],"main_file_link":[{"url":"https://www.nature.com/articles/s41467-026-74861-9","open_access":"1"}],"article_number":"5683","intvolume":"        17","article_type":"original","date_updated":"2026-07-01T08:15:21Z","publication_status":"published","author":[{"id":"88928","last_name":"Pegoraro","first_name":"Federico","full_name":"Pegoraro, Federico"},{"id":"68236","last_name":"Held","first_name":"Philip","full_name":"Held, Philip"},{"full_name":"Lammers, Jonas","last_name":"Lammers","first_name":"Jonas"},{"last_name":"Brecht","orcid":"0000-0003-4140-0556 ","first_name":"Benjamin","full_name":"Brecht, Benjamin","id":"27150"},{"id":"26263","last_name":"Silberhorn","first_name":"Christine","full_name":"Silberhorn, Christine"}],"publication_identifier":{"issn":["2041-1723"]},"year":"2026","title":"Demonstration of a quantum C-NOT gate in a time-multiplexed fully reconfigurable photonic processor","oa":"1","citation":{"bibtex":"@article{Pegoraro_Held_Lammers_Brecht_Silberhorn_2026, title={Demonstration of a quantum C-NOT gate in a time-multiplexed fully reconfigurable photonic processor}, volume={17}, DOI={<a href=\"https://doi.org/10.1038/s41467-026-74861-9\">10.1038/s41467-026-74861-9</a>}, number={15683}, journal={Nature Communications}, publisher={Springer Science and Business Media LLC}, author={Pegoraro, Federico and Held, Philip and Lammers, Jonas and Brecht, Benjamin and Silberhorn, Christine}, year={2026} }","ama":"Pegoraro F, Held P, Lammers J, Brecht B, Silberhorn C. Demonstration of a quantum C-NOT gate in a time-multiplexed fully reconfigurable photonic processor. <i>Nature Communications</i>. 2026;17(1). doi:<a href=\"https://doi.org/10.1038/s41467-026-74861-9\">10.1038/s41467-026-74861-9</a>","mla":"Pegoraro, Federico, et al. “Demonstration of a Quantum C-NOT Gate in a Time-Multiplexed Fully Reconfigurable Photonic Processor.” <i>Nature Communications</i>, vol. 17, no. 1, 5683, Springer Science and Business Media LLC, 2026, doi:<a href=\"https://doi.org/10.1038/s41467-026-74861-9\">10.1038/s41467-026-74861-9</a>.","short":"F. Pegoraro, P. Held, J. Lammers, B. Brecht, C. Silberhorn, Nature Communications 17 (2026).","chicago":"Pegoraro, Federico, Philip Held, Jonas Lammers, Benjamin Brecht, and Christine Silberhorn. “Demonstration of a Quantum C-NOT Gate in a Time-Multiplexed Fully Reconfigurable Photonic Processor.” <i>Nature Communications</i> 17, no. 1 (2026). <a href=\"https://doi.org/10.1038/s41467-026-74861-9\">https://doi.org/10.1038/s41467-026-74861-9</a>.","ieee":"F. Pegoraro, P. Held, J. Lammers, B. Brecht, and C. Silberhorn, “Demonstration of a quantum C-NOT gate in a time-multiplexed fully reconfigurable photonic processor,” <i>Nature Communications</i>, vol. 17, no. 1, Art. no. 5683, 2026, doi: <a href=\"https://doi.org/10.1038/s41467-026-74861-9\">10.1038/s41467-026-74861-9</a>.","apa":"Pegoraro, F., Held, P., Lammers, J., Brecht, B., &#38; Silberhorn, C. (2026). Demonstration of a quantum C-NOT gate in a time-multiplexed fully reconfigurable photonic processor. <i>Nature Communications</i>, <i>17</i>(1), Article 5683. <a href=\"https://doi.org/10.1038/s41467-026-74861-9\">https://doi.org/10.1038/s41467-026-74861-9</a>"},"volume":17,"user_id":"88928","publisher":"Springer Science and Business Media LLC","_id":"66094","status":"public"},{"status":"public","volume":31,"user_id":"63231","publisher":"Optica Publishing Group","_id":"45850","citation":{"bibtex":"@article{Babel_Bollmers_Massaro_Luo_Stefszky_Pegoraro_Held_Herrmann_Eigner_Brecht_et al._2023, title={Demonstration of Hong-Ou-Mandel interference in an LNOI directional coupler}, volume={31}, DOI={<a href=\"https://doi.org/10.1364/oe.484126\">10.1364/oe.484126</a>}, number={1423140}, journal={Optics Express}, publisher={Optica Publishing Group}, author={Babel, Silia and Bollmers, Laura and Massaro, Marcello and Luo, Kai Hong and Stefszky, Michael and Pegoraro, Federico and Held, Philip and Herrmann, Harald and Eigner, Christof and Brecht, Benjamin and et al.}, year={2023} }","ama":"Babel S, Bollmers L, Massaro M, et al. Demonstration of Hong-Ou-Mandel interference in an LNOI directional coupler. <i>Optics Express</i>. 2023;31(14). doi:<a href=\"https://doi.org/10.1364/oe.484126\">10.1364/oe.484126</a>","mla":"Babel, Silia, et al. “Demonstration of Hong-Ou-Mandel Interference in an LNOI Directional Coupler.” <i>Optics Express</i>, vol. 31, no. 14, 23140, Optica Publishing Group, 2023, doi:<a href=\"https://doi.org/10.1364/oe.484126\">10.1364/oe.484126</a>.","short":"S. Babel, L. Bollmers, M. Massaro, K.H. Luo, M. Stefszky, F. Pegoraro, P. Held, H. Herrmann, C. Eigner, B. Brecht, L. Padberg, C. Silberhorn, Optics Express 31 (2023).","chicago":"Babel, Silia, Laura Bollmers, Marcello Massaro, Kai Hong Luo, Michael Stefszky, Federico Pegoraro, Philip Held, et al. “Demonstration of Hong-Ou-Mandel Interference in an LNOI Directional Coupler.” <i>Optics Express</i> 31, no. 14 (2023). <a href=\"https://doi.org/10.1364/oe.484126\">https://doi.org/10.1364/oe.484126</a>.","ieee":"S. Babel <i>et al.</i>, “Demonstration of Hong-Ou-Mandel interference in an LNOI directional coupler,” <i>Optics Express</i>, vol. 31, no. 14, Art. no. 23140, 2023, doi: <a href=\"https://doi.org/10.1364/oe.484126\">10.1364/oe.484126</a>.","apa":"Babel, S., Bollmers, L., Massaro, M., Luo, K. H., Stefszky, M., Pegoraro, F., Held, P., Herrmann, H., Eigner, C., Brecht, B., Padberg, L., &#38; Silberhorn, C. (2023). Demonstration of Hong-Ou-Mandel interference in an LNOI directional coupler. <i>Optics Express</i>, <i>31</i>(14), Article 23140. <a href=\"https://doi.org/10.1364/oe.484126\">https://doi.org/10.1364/oe.484126</a>"},"intvolume":"        31","date_updated":"2023-07-05T07:58:31Z","publication_status":"published","author":[{"full_name":"Babel, Silia","last_name":"Babel","orcid":"https://orcid.org/0000-0002-1568-2580","first_name":"Silia","id":"63231"},{"id":"61375","first_name":"Laura","last_name":"Bollmers","full_name":"Bollmers, Laura"},{"id":"59545","first_name":"Marcello","orcid":"0000-0002-2539-7652","last_name":"Massaro","full_name":"Massaro, Marcello"},{"full_name":"Luo, Kai Hong","first_name":"Kai Hong","orcid":"0000-0003-1008-4976","last_name":"Luo","id":"36389"},{"id":"42777","full_name":"Stefszky, Michael","first_name":"Michael","last_name":"Stefszky"},{"last_name":"Pegoraro","first_name":"Federico","full_name":"Pegoraro, Federico","id":"88928"},{"first_name":"Philip","last_name":"Held","full_name":"Held, Philip","id":"68236"},{"id":"216","full_name":"Herrmann, Harald","last_name":"Herrmann","first_name":"Harald"},{"id":"13244","orcid":"https://orcid.org/0000-0002-5693-3083","first_name":"Christof","last_name":"Eigner","full_name":"Eigner, Christof"},{"last_name":"Brecht","orcid":"0000-0003-4140-0556 ","first_name":"Benjamin","full_name":"Brecht, Benjamin","id":"27150"},{"full_name":"Padberg, Laura","last_name":"Padberg","first_name":"Laura","id":"40300"},{"id":"26263","first_name":"Christine","last_name":"Silberhorn","full_name":"Silberhorn, Christine"}],"publication_identifier":{"issn":["1094-4087"]},"year":"2023","title":"Demonstration of Hong-Ou-Mandel interference in an LNOI directional coupler","doi":"10.1364/oe.484126","language":[{"iso":"eng"}],"article_number":"23140","abstract":[{"lang":"eng","text":"Interference between single photons is key for many quantum optics experiments and applications in quantum technologies, such as quantum communication or computation. It is advantageous to operate the systems at telecommunication wavelengths and to integrate the setups for these applications in order to improve stability, compactness and scalability. A new promising material platform for integrated quantum optics is lithium niobate on insulator (LNOI). Here, we realise Hong-Ou-Mandel (HOM) interference between telecom photons from an engineered parametric down-conversion source in an LNOI directional coupler. The coupler has been designed and fabricated in house and provides close to perfect balanced beam splitting. We obtain a raw HOM visibility of (93.5 ± 0.7) %, limited mainly by the source performance and in good agreement with off-chip measurements. This lays the foundation for more sophisticated quantum experiments in LNOI."}],"issue":"14","publication":"Optics Express","department":[{"_id":"15"},{"_id":"230"},{"_id":"623"},{"_id":"288"}],"keyword":["Atomic and Molecular Physics","and Optics"],"type":"journal_article","date_created":"2023-07-03T14:08:36Z"},{"status":"public","publisher":"IOP Publishing","_id":"42648","user_id":"68236","volume":98,"citation":{"ama":"Pegoraro F, Held P, Barkhofen S, Brecht B, Silberhorn C. Dynamic conditioning of two particle discrete-time quantum walks. <i>Physica Scripta</i>. 2023;98(3). doi:<a href=\"https://doi.org/10.1088/1402-4896/acbcaa\">10.1088/1402-4896/acbcaa</a>","bibtex":"@article{Pegoraro_Held_Barkhofen_Brecht_Silberhorn_2023, title={Dynamic conditioning of two particle discrete-time quantum walks}, volume={98}, DOI={<a href=\"https://doi.org/10.1088/1402-4896/acbcaa\">10.1088/1402-4896/acbcaa</a>}, number={3034005}, journal={Physica Scripta}, publisher={IOP Publishing}, author={Pegoraro, Federico and Held, Philip and Barkhofen, Sonja and Brecht, Benjamin and Silberhorn, Christine}, year={2023} }","mla":"Pegoraro, Federico, et al. “Dynamic Conditioning of Two Particle Discrete-Time Quantum Walks.” <i>Physica Scripta</i>, vol. 98, no. 3, 034005, IOP Publishing, 2023, doi:<a href=\"https://doi.org/10.1088/1402-4896/acbcaa\">10.1088/1402-4896/acbcaa</a>.","short":"F. Pegoraro, P. Held, S. Barkhofen, B. Brecht, C. Silberhorn, Physica Scripta 98 (2023).","chicago":"Pegoraro, Federico, Philip Held, Sonja Barkhofen, Benjamin Brecht, and Christine Silberhorn. “Dynamic Conditioning of Two Particle Discrete-Time Quantum Walks.” <i>Physica Scripta</i> 98, no. 3 (2023). <a href=\"https://doi.org/10.1088/1402-4896/acbcaa\">https://doi.org/10.1088/1402-4896/acbcaa</a>.","apa":"Pegoraro, F., Held, P., Barkhofen, S., Brecht, B., &#38; Silberhorn, C. (2023). Dynamic conditioning of two particle discrete-time quantum walks. <i>Physica Scripta</i>, <i>98</i>(3), Article 034005. <a href=\"https://doi.org/10.1088/1402-4896/acbcaa\">https://doi.org/10.1088/1402-4896/acbcaa</a>","ieee":"F. Pegoraro, P. Held, S. Barkhofen, B. Brecht, and C. Silberhorn, “Dynamic conditioning of two particle discrete-time quantum walks,” <i>Physica Scripta</i>, vol. 98, no. 3, Art. no. 034005, 2023, doi: <a href=\"https://doi.org/10.1088/1402-4896/acbcaa\">10.1088/1402-4896/acbcaa</a>."},"oa":"1","year":"2023","title":"Dynamic conditioning of two particle discrete-time quantum walks","author":[{"id":"88928","full_name":"Pegoraro, Federico","last_name":"Pegoraro","first_name":"Federico"},{"full_name":"Held, Philip","first_name":"Philip","last_name":"Held","id":"68236"},{"id":"48188","last_name":"Barkhofen","first_name":"Sonja","full_name":"Barkhofen, Sonja"},{"orcid":"0000-0003-4140-0556 ","last_name":"Brecht","first_name":"Benjamin","full_name":"Brecht, Benjamin","id":"27150"},{"last_name":"Silberhorn","first_name":"Christine","full_name":"Silberhorn, Christine","id":"26263"}],"publication_identifier":{"issn":["0031-8949","1402-4896"]},"date_updated":"2026-01-09T09:49:31Z","publication_status":"published","intvolume":"        98","article_type":"original","main_file_link":[{"open_access":"1","url":"https://iopscience.iop.org/article/10.1088/1402-4896/acbcaa"}],"article_number":"034005","language":[{"iso":"eng"}],"doi":"10.1088/1402-4896/acbcaa","issue":"3","publication":"Physica Scripta","abstract":[{"text":"In real photonic quantum systems losses are an unavoidable factor limiting the scalability to many modes and particles, restraining their application in fields as quantum information and communication. For this reason, a considerable amount of engineering effort has been taken in order to improve the quality of particle sources and system components. At the same time, data analysis and collection methods based on post-selection have been used to mitigate the effect of particle losses. This has allowed for investigating experimentally multi-particle evolutions where the observer lacks knowledge about the system's intermediate propagation states. Nonetheless, the fundamental question how losses affect the behaviour of the surviving subset of a multi-particle system has not been investigated so far. For this reason, here we study the impact of particle losses in a quantum walk of two photons reconstructing the output probability distributions for one photon conditioned on the loss of the other in a known mode and temporal step of our evolution network. We present the underlying theoretical scheme that we have devised in order to model controlled particle losses, we describe an experimental platform capable of implementing our theory in a time multiplexing encoding. In the end we show how localized particle losses change the output distributions without altering their asymptotic spreading properties. Finally we devise a quantum civilization problem, a two walker generalisation of single particle recurrence processes.","lang":"eng"}],"date_created":"2023-03-02T09:53:59Z","type":"journal_article","department":[{"_id":"623"},{"_id":"15"},{"_id":"288"},{"_id":"169"}]}]