{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T19:05:45Z","timestamp":1772564745068,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2016,12,21]],"date-time":"2016-12-21T00:00:00Z","timestamp":1482278400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/summer-heart-0930.chufeiyun1688.workers.dev:443\/https\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61340032, 61535010"],"award-info":[{"award-number":["61340032, 61535010"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Key Research Program of the Chinese Academy of Sciences","award":["KFZD-SW-204"],"award-info":[{"award-number":["KFZD-SW-204"]}]},{"DOI":"10.13039\/501100004608","name":"Natural Science Foundation of Jiangsu Province","doi-asserted-by":"publisher","award":["BE2015601"],"award-info":[{"award-number":["BE2015601"]}],"id":[{"id":"10.13039\/501100004608","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007129","name":"Natural Science Foundation of Shandong Province","doi-asserted-by":"publisher","award":["ZR2012CM029"],"award-info":[{"award-number":["ZR2012CM029"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Key Research Development Program of Shandong Province","award":["2015GSF117024, 2015GSF121047"],"award-info":[{"award-number":["2015GSF117024, 2015GSF121047"]}]},{"name":"Independent Innovation Achievement Transformation Project of Shandong Province, China","award":["2014ZZCX02602"],"award-info":[{"award-number":["2014ZZCX02602"]}]},{"name":"the Science and Technology Department of Suzhou City","award":["SS201539, ZXY201434"],"award-info":[{"award-number":["SS201539, ZXY201434"]}]},{"name":"the 863 Program","award":["2015AA021005"],"award-info":[{"award-number":["2015AA021005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The response of a novel long-period fiber grating (LPFG) with a period of 180 \u00b5m to a surrounding refractive index (RI) was investigated. The results displayed that, with the increase in RI of the surrounding media of cladding glass in the grating region, the resonant peak located at 1336.4 nm in the transmission spectrum gradually shifts towards a shorter wavelength, while the resonant peak located at 1618 nm gradually shifted towards a longer wavelength. Moreover, the resonant peak at 1618 nm is much more sensitive to the surrounding RI than that of the one at 1336.4 nm. Compared with the conventional LPFG and other types of wavelength-interrogated RI sensors, such as ring resonators, surface plasmon resonance sensors, and Fabry\u2013Perot interferometric sensors, this novel LPFG possesses a higher sensitivity, which achieved 10,792.45 nm\/RIU (RI unit) over a RI range of 1.4436\u20131.4489.<\/jats:p>","DOI":"10.3390\/s16122205","type":"journal-article","created":{"date-parts":[[2016,12,23]],"date-time":"2016-12-23T04:09:09Z","timestamp":1482466149000},"page":"2205","update-policy":"https:\/\/summer-heart-0930.chufeiyun1688.workers.dev:443\/https\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["An Ultrasensitive Long-Period Fiber Grating-Based Refractive Index Sensor with Long Wavelengths"],"prefix":"10.3390","volume":"16","author":[{"given":"Qiu-Shun","family":"Li","sequence":"first","affiliation":[{"name":"Key Biosensor Laboratory of Shandong Province, Biology Institute of Shandong Academy of Sciences, Jinan 250014, China"}]},{"given":"Xu-Lin","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China"}]},{"given":"Jian-Guo","family":"Shi","sequence":"additional","affiliation":[{"name":"Key Biosensor Laboratory of Shandong Province, Biology Institute of Shandong Academy of Sciences, Jinan 250014, China"}]},{"given":"Dong","family":"Xiang","sequence":"additional","affiliation":[{"name":"CAS Key Laboratory of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China"}]},{"given":"Lan","family":"Zheng","sequence":"additional","affiliation":[{"name":"Key Biosensor Laboratory of Shandong Province, Biology Institute of Shandong Academy of Sciences, Jinan 250014, China"}]},{"given":"Yan","family":"Yang","sequence":"additional","affiliation":[{"name":"Key Biosensor Laboratory of Shandong Province, Biology Institute of Shandong Academy of Sciences, Jinan 250014, China"}]},{"given":"Jun-Hui","family":"Yang","sequence":"additional","affiliation":[{"name":"Key Biosensor Laboratory of Shandong Province, Biology Institute of Shandong Academy of Sciences, Jinan 250014, China"}]},{"given":"Dong","family":"Feng","sequence":"additional","affiliation":[{"name":"Key Biosensor Laboratory of Shandong Province, Biology Institute of Shandong Academy of Sciences, Jinan 250014, China"}]},{"given":"Wen-Fei","family":"Dong","sequence":"additional","affiliation":[{"name":"CAS Key Laboratory of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China"}]}],"member":"1968","published-online":{"date-parts":[[2016,12,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"R49","DOI":"10.1088\/0957-0233\/14\/5\/201","article-title":"Optical fibre long-period grating sensors: Characteristics and application","volume":"14","author":"James","year":"2003","journal-title":"Meas. 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