{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T02:50:20Z","timestamp":1787626220927,"version":"build-2736575974"},"reference-count":35,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T00:00:00Z","timestamp":1769644800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["82201638"],"award-info":[{"award-number":["82201638"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"2024 International Cooperation Seed Funding Project for China\u2019s Ocean Decade Actions","award":["GHZZ3702840002024020000032"],"award-info":[{"award-number":["GHZZ3702840002024020000032"]}]},{"DOI":"10.13039\/501100007129","name":"Shandong Provincial Natural Science Foundation","doi-asserted-by":"crossref","award":["ZR2025MS827"],"award-info":[{"award-number":["ZR2025MS827"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100007129","name":"Shandong Provincial Natural Science Foundation","doi-asserted-by":"crossref","award":["ZR2024QE212"],"award-info":[{"award-number":["ZR2024QE212"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100007129","name":"Shandong Provincial Natural Science Foundation","doi-asserted-by":"crossref","award":["ZR2024QH638"],"award-info":[{"award-number":["ZR2024QH638"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Shandong Youth Innovation and Technology Support Program","award":["2024KJJ040"],"award-info":[{"award-number":["2024KJJ040"]}]},{"DOI":"10.13039\/501100014761","name":"Qingdao Municipal Natural Science Foundation","doi-asserted-by":"publisher","award":["24-4-4-zrjj-99-jch"],"award-info":[{"award-number":["24-4-4-zrjj-99-jch"]}],"id":[{"id":"10.13039\/501100014761","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>The development of high-performance optical fiber sensors based on surface plasmon resonance (SPR) represents a significant advancement in precision detection technology, particularly for biomedical and environmental monitoring applications requiring real-time response and minimal sample consumption. This research conducts a systematic numerical investigation of a D-shaped fiber SPR sensor incorporating an optimized silver-hematite (Ag-\u03b1-Fe2O3) composite grating structure. Through comprehensive finite element simulations and parameter analysis, we demonstrate that controlling the silver layer thickness at 45 nm while maintaining the \u03b1-Fe2O3 thickness at 12 nm achieves optimal electric field confinement. The grating gap width optimization at 30 nm enables maximum sensitivity through enhanced localized surface plasmon resonance effects, while the residual cladding thickness of 0.5 \u03bcm provides the ideal balance between detection accuracy and sensitivity. The research establishes fundamental design principles for high-performance SPR sensors by elucidating the critical relationships between geometric parameters and sensing characteristics, providing valuable insights for developing next-generation sensors with enhanced performance for advanced sensing applications in environmental monitoring and medical diagnostics.<\/jats:p>","DOI":"10.3390\/mi17020183","type":"journal-article","created":{"date-parts":[[2026,1,29]],"date-time":"2026-01-29T10:56:34Z","timestamp":1769684194000},"page":"183","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Enhanced Sensitivity in D-Shaped Optical Fiber SPR Sensor via Ag-\u03b1-Fe2O3 Grating"],"prefix":"10.3390","volume":"17","author":[{"given":"Shuai","family":"Yuan","sequence":"first","affiliation":[{"name":"School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao 266113, China"},{"name":"Ocean Decade International Cooperation Center (ODCC), Qingdao 266520, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-7331-0235","authenticated-orcid":false,"given":"Bingyang","family":"Yuan","sequence":"additional","affiliation":[{"name":"School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao 266113, China"},{"name":"College of Shipbuilding Engineering, Harbin Engineering University, Harbin 150001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1802-3123","authenticated-orcid":false,"given":"Jiu","family":"Deng","sequence":"additional","affiliation":[{"name":"School of Health and Life Sciences, University of Health and Rehabilitation Sciences, Qingdao 266113, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"343743","DOI":"10.1016\/j.aca.2025.343743","article-title":"Immunofluorescent Analysis of Exosomes Using a Microchip Filled with Transparent Antibody-Conjugated Beads for Breast Cancer Liquid Biopsy","volume":"1345","author":"Li","year":"2025","journal-title":"Anal. 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