{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T05:15:40Z","timestamp":1788412540628,"version":"build-2803163510"},"reference-count":26,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T00:00:00Z","timestamp":1787961600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100019370","name":"Foundation for Science and Technology","doi-asserted-by":"publisher","award":["UID\/PRR2\/00066\/2025"],"award-info":[{"award-number":["UID\/PRR2\/00066\/2025"]}],"id":[{"id":"10.13039\/501100019370","id-type":"DOI","asserted-by":"publisher"}]},{"award":["UID\/PRR2\/00066\/2025"],"award-info":[{"award-number":["UID\/PRR2\/00066\/2025"]}],"id":[{"id":"https:\/\/ror.org\/00snfqn58","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>In this work, we present the design and numerical validation of a reconfigurable electro-optic photonic integrated circuit architecture for dynamic 1 \u00d7 4 optical routing, based on electro-optic phase shifters and a chain of cascaded multimode interference structures, and implemented in an amorphous silicon platform. By exploiting recent developments in symmetry-engineered silicon photonics to enable phase control in a platform compatible with complementary metal-oxide-semiconductor fabrication requirements, this approach addresses the increasing demand for ultra-fast, compact and energy efficient reconfigurable photonic integrated circuits. The photonic circuit design bases its functionality on self-imaging theory and has been optimized through simulations implementing the beam propagation method, while optical performance and electro-optical behavior have been validated through finite difference time-domain simulations and multiphysics modeling. The numerical results obtained confirm the operational performance of the individual building blocks and demonstrate the proposed architecture as being able to perform as a reconfigurable electro-optic platform and provide the dynamic 1 \u00d7 4 optical routing. Hence, this architecture provides a scalable platform for reconfigurable silicon photonics, complementary metal-oxide-semiconductor compatible, and the fabrication-ready layout establishes a practical path to experimental validation and future reconfigurable photonic integrated circuits.<\/jats:p>","DOI":"10.3390\/mi17091035","type":"journal-article","created":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T02:08:58Z","timestamp":1788142138000},"page":"1035","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["A Reconfigurable Electro-Optic Photonic Integrated Circuit Architecture"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8785-445X","authenticated-orcid":false,"given":"Paulo","family":"Louren\u00e7o","sequence":"first","affiliation":[{"name":"Instituto Superior de Engenharia de Lisboa (ISEL), Polytechnic University of Lisbon, 1549-020 Lisboa, Portugal"},{"name":"Center of Technology and Systems (CTS) and Associated Lab of Intelligent Systems (LASI), 2829-516 Caparica, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-6076-1146","authenticated-orcid":false,"given":"Andr\u00e9","family":"Moreira","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia de Lisboa (ISEL), Polytechnic University of Lisbon, 1549-020 Lisboa, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ernesto","family":"Vel\u00e1zquez","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia de Lisboa (ISEL), Polytechnic University of Lisbon, 1549-020 Lisboa, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9938-0351","authenticated-orcid":false,"given":"Alessandro","family":"Fantoni","sequence":"additional","affiliation":[{"name":"Instituto Superior de Engenharia de Lisboa (ISEL), Polytechnic University of Lisbon, 1549-020 Lisboa, Portugal"},{"name":"Center of Technology and Systems (CTS) and Associated Lab of Intelligent Systems (LASI), 2829-516 Caparica, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"751","DOI":"10.1038\/s41467-024-44750-0","article-title":"Roadmapping the next generation of silicon photonics","volume":"15","author":"Shekhar","year":"2024","journal-title":"Nat. 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