{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,27]],"date-time":"2026-03-27T16:36:25Z","timestamp":1774629385486,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,7,29]],"date-time":"2022-07-29T00:00:00Z","timestamp":1659052800000},"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":["61875247"],"award-info":[{"award-number":["61875247"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31805180101"],"award-info":[{"award-number":["31805180101"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["319190301"],"award-info":[{"award-number":["319190301"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Liaocheng University","award":["61875247"],"award-info":[{"award-number":["61875247"]}]},{"name":"Liaocheng University","award":["31805180101"],"award-info":[{"award-number":["31805180101"]}]},{"name":"Liaocheng University","award":["319190301"],"award-info":[{"award-number":["319190301"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Bending sensing was realized by constructing a tapered four-core optical fiber (TFCF) sensor. The four-core fiber (FCF) between the fan-in and fan-out couplers was tapered and the diameter became smaller, so that the distance between the four cores arranged in a square became gradually smaller to produce supermodes. The two ends of the TFCF were respectively connected to the fan-in and fan-out couplers so that the individual cores in the FCF could link to the separate single-mode fibers. A broadband light source (superluminescent diodes (SLD)) spanning 1250\u20131650 nm was injected into any one of the four cores, and the orientation was thus determined. In the tapering process, the remaining three cores gradually approached the excitation core in space to excite several supermodes based on the tri-core structure first, and then transited to the quadruple-core structure. The field distributions of the excited supermodes were asymmetric due to the corner-core excitation scheme, and the interference thus resulted in a higher measurement sensitivity. When the diameter of the TFCF was 7.5 \u03bcm and the tapered length was 2.21 mm, the sensitivity of the bending sensor could reach 16.12 nm\/m\u22121.<\/jats:p>","DOI":"10.3390\/s22155698","type":"journal-article","created":{"date-parts":[[2022,8,1]],"date-time":"2022-08-01T23:49:27Z","timestamp":1659397767000},"page":"5698","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Multicore Fiber Bending Sensors with High Sensitivity Based on Asymmetric Excitation Scheme"],"prefix":"10.3390","volume":"22","author":[{"given":"Lina","family":"Suo","sequence":"first","affiliation":[{"name":"School of Physics Sciences and Information Technology, Liaocheng University, Liaocheng 252000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5429-6896","authenticated-orcid":false,"given":"Ya-Pei","family":"Peng","sequence":"additional","affiliation":[{"name":"College of Engineering Physics, Shenzhen Technology University, Shenzhen 518000, China"},{"name":"NK Photonics Ltd., Jinan 250119, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nan-Kuang","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Physics Sciences and Information Technology, Liaocheng University, Liaocheng 252000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"871","DOI":"10.1617\/s11527-013-0201-7","article-title":"Review: Optical fifiber sensors for civil engineering applications","volume":"48","author":"Leung","year":"2015","journal-title":"Mater. 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