{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,10]],"date-time":"2026-05-10T02:46:11Z","timestamp":1778381171247,"version":"3.51.4"},"reference-count":26,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2012,5,30]],"date-time":"2012-05-30T00:00:00Z","timestamp":1338336000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A simple and high sensitive method employing a hybrid long period grating (LPG)\/chirped fiber Bragg grating (CFBG) for refractive index (RI) measurements is proposed and investigated experimentally. The wide wavelength range of backward cladding modes are excited through the coupling and recoupling between LPG and CFBG. Experimental results indicate that the recoupled cladding modes between LPG and CFBG and core mode are modulated by the surrounding RI and highly sensitive RI measurements can be achieved by simply measuring the reflected intensity changes of the recoupled cladding modes and core mode.<\/jats:p>","DOI":"10.3390\/s120607318","type":"journal-article","created":{"date-parts":[[2012,5,30]],"date-time":"2012-05-30T11:08:12Z","timestamp":1338376092000},"page":"7318-7325","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["A Hybrid LPG\/CFBG for Highly Sensitive Refractive Index Measurements"],"prefix":"10.3390","volume":"12","author":[{"given":"An","family":"Sun","sequence":"first","affiliation":[{"name":"International Institute for Urban Systems Engineering, Southeast University, Nanjing 210096, Jiangsu, China"}]},{"given":"Zhishen","family":"Wu","sequence":"additional","affiliation":[{"name":"International Institute for Urban Systems Engineering, Southeast University, Nanjing 210096, Jiangsu, China"}]}],"member":"1968","published-online":{"date-parts":[[2012,5,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1606","DOI":"10.1109\/50.712243","article-title":"Analysis of the response of long period fiber gratings to external index of refraction","volume":"16","author":"Patrick","year":"1998","journal-title":"J. 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