{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,27]],"date-time":"2026-05-27T15:17:55Z","timestamp":1779895075970,"version":"3.53.1"},"reference-count":27,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,12,24]],"date-time":"2019-12-24T00:00:00Z","timestamp":1577145600000},"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":["61675137, 91860138"],"award-info":[{"award-number":["61675137, 91860138"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Science and Technology Innovation Commission of Shenzhen","award":["JCYJ20170818093743767, JCYJ20180507183904841"],"award-info":[{"award-number":["JCYJ20170818093743767, JCYJ20180507183904841"]}]},{"name":"Development and Reform Commission of Shenzhen Municipality Foundation","award":["."],"award-info":[{"award-number":["."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A high sensitivity fiber-optic sensor based on self-imaging effect in a hollow-core capillary waveguide (HCCW) is presented for sensing applications. The sensor is composed of a section of HCCW fusion spliced between single mode fibers (SMFs). The self-imaging effect in the HCCW is investigated with different fiber lengths and arc-fusion parameters. By infiltrating the hollow core with index matching liquids, the peak wavelength of the proposed device shifts towards longer wavelengths. The temperature and refractive index (RI) responses of the sensor are studied systematically. When temperature is increased from 25 \u00b0C to 75 \u00b0C, the temperature sensitivity of the device can be improved significantly with the infiltrated structure, and reaches \u22120.49 nm\/\u00b0C, compared with that of the un-filled device, which is 9.8 pm\/\u00b0C. For the RI response, the liquid-filled structure achieves sensitivity of 12,005 nm\/RIU in the range between 1.448 and 1.450, slightly higher than the 11,920 nm\/RIU achieved by the un-filled one. The proposed sensor exhibits the advantages of simple structure, high sensitivity and low cost, which may find potential applications in physical and chemical sensing.<\/jats:p>","DOI":"10.3390\/s20010135","type":"journal-article","created":{"date-parts":[[2019,12,24]],"date-time":"2019-12-24T10:28:43Z","timestamp":1577183323000},"page":"135","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Self-Imaging Effect in Liquid-Filled Hollow-Core Capillary Waveguide for Sensing Applications"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4337-956X","authenticated-orcid":false,"given":"Yijian","family":"Huang","sequence":"first","affiliation":[{"name":"Guangdong and Hong Kong Joint Research Centre for Optical Fibre Sensors, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China"},{"name":"Guangdong Laboratory of Artificial Intelligence and Digital Economy, Shenzhen University, Shenzhen 518060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuhui","family":"Liu","sequence":"additional","affiliation":[{"name":"Guangdong and Hong Kong Joint Research Centre for Optical Fibre Sensors, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China"},{"name":"Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lichao","family":"Zhang","sequence":"additional","affiliation":[{"name":"Guangdong and Hong Kong Joint Research Centre for Optical Fibre Sensors, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China"},{"name":"Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yiping","family":"Wang","sequence":"additional","affiliation":[{"name":"Guangdong and Hong Kong Joint Research Centre for Optical Fibre Sensors, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China"},{"name":"Guangdong Laboratory of Artificial Intelligence and Digital Economy, Shenzhen University, Shenzhen 518060, China"},{"name":"Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ying","family":"Wang","sequence":"additional","affiliation":[{"name":"Guangdong and Hong Kong Joint Research Centre for Optical Fibre Sensors, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China"},{"name":"Guangdong Laboratory of Artificial Intelligence and Digital Economy, Shenzhen University, Shenzhen 518060, China"},{"name":"Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, Shenzhen University, Shenzhen 518060, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2700","DOI":"10.1109\/LPT.2005.859400","article-title":"Simultaneous measurement of refractive index and temperature using a single ultralong-period fiber grating","volume":"17","author":"Zhu","year":"2005","journal-title":"IEEE Photonics Technol. 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