{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T03:20:56Z","timestamp":1768447256817,"version":"3.49.0"},"reference-count":39,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,2,7]],"date-time":"2021-02-07T00:00:00Z","timestamp":1612656000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Herein, we propose a tunable plasmonic sensor with Fano resonators in an inverted U-shaped resonator. By manipulating the sharp asymmetric Fano resonance peaks, a high-sensitivity refractive index sensor can be realized. Using the multimode interference coupled-mode theory and the finite element method, we numerically simulate the influences of geometrical parameters on the plasmonic sensor. Optimizing the structure parameters, we can achieve a high plasmonic sensor with the maximum sensitivity for 840 nm\/RIUand figure of merit for 3.9 \u00d7 105. The research results provide a reliable theoretical basis for designing high sensitivity to the next generation plasmonic nanosensor.<\/jats:p>","DOI":"10.3390\/s21041164","type":"journal-article","created":{"date-parts":[[2021,2,10]],"date-time":"2021-02-10T04:33:46Z","timestamp":1612931626000},"page":"1164","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["High Sensitivity Plasmonic Sensor Based on Fano Resonance with Inverted U-Shaped Resonator"],"prefix":"10.3390","volume":"21","author":[{"given":"Gongli","family":"Xiao","sequence":"first","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}]},{"given":"Yanping","family":"Xu","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7452-9658","authenticated-orcid":false,"given":"Hongyan","family":"Yang","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin 541004, China"},{"name":"School of Electronic Engineering and Automation, Guilin University of Electronic Technology, Guilin 541004, China"}]},{"given":"Zetao","family":"Ou","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}]},{"given":"Jianyun","family":"Chen","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}]},{"given":"Haiou","family":"Li","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}]},{"given":"Xingpeng","family":"Liu","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}]},{"given":"Lizhen","family":"Zeng","sequence":"additional","affiliation":[{"name":"Graduate School, Guilin University of Electronic Technology, Guilin 541004, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6768-1483","authenticated-orcid":false,"given":"Jianqing","family":"Li","sequence":"additional","affiliation":[{"name":"Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology, Foshan University, Foshan 528225, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1016\/S0925-4005(98)00321-9","article-title":"Surface plasmon resonance sensors","volume":"54","author":"Homola","year":"1999","journal-title":"Sens. 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