{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T20:41:22Z","timestamp":1774384882493,"version":"3.50.1"},"reference-count":21,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2019,11,21]],"date-time":"2019-11-21T00:00:00Z","timestamp":1574294400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FIOSRAIGH 2016 Dean of Graduate Students Award, TU Dublin, Ireland","award":["000000"],"award-info":[{"award-number":["000000"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper we propose and investigate a novel magnetic field sensor based on a Tri-microfiber coupler combined with magnetic fluid and a fiber Bragg grating (FBG) in a ring. A sensitivity of 1306 pm\/mT was experimentally demonstrated in the range of magnetic fields from 0 to 15 mT. The reflection peak in the output spectrum associated with the FBG serves as a reference point allowing to avoid ambiguity in determining the spectral shift induced by the magnetic field. Due to its high sensitivity at low magnetic fields, the proposed structure could be of high interest in low field biosensing applications that involve a magnetic field, such as magnetic manipulation or separation of biomolecules.<\/jats:p>","DOI":"10.3390\/s19235100","type":"journal-article","created":{"date-parts":[[2019,11,22]],"date-time":"2019-11-22T02:49:27Z","timestamp":1574390967000},"page":"5100","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":25,"title":["Magnetic Field Sensor Based on a Tri-Microfiber Coupler Ring in Magnetic Fluid and a Fiber Bragg Grating"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1536-9452","authenticated-orcid":false,"given":"Fangfang","family":"Wei","sequence":"first","affiliation":[{"name":"Photonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, Kevin St, D08 X622 Dublin, Ireland"}]},{"given":"Dejun","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, Guangdong, China"}]},{"given":"Arun Kumar","family":"Mallik","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, Kevin St, D08 X622 Dublin, Ireland"}]},{"given":"Gerald","family":"Farrel","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, Kevin St, D08 X622 Dublin, Ireland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2901-7434","authenticated-orcid":false,"given":"Qiang","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle Upon Tyne NE1 8ST, UK"}]},{"given":"Gang-Ding","family":"Peng","sequence":"additional","affiliation":[{"name":"Photonics &amp; Optical Communications, School of Electrical Engineering &amp; Telecommunications, University of New South Wales, Sydney 2052, Australia"}]},{"given":"Yuliya","family":"Semenova","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, Kevin St, D08 X622 Dublin, Ireland"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Alberto, N., Domingues, M.F., Marques, C., Andr\u00e9, P., and Antunes, P. 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