{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T04:33:15Z","timestamp":1777350795335,"version":"3.51.4"},"reference-count":35,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,4,20]],"date-time":"2023-04-20T00:00:00Z","timestamp":1681948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Science technology plan of ShaanXi","award":["2020GY-187"],"award-info":[{"award-number":["2020GY-187"]}]},{"name":"Science technology plan of ShaanXi","award":["CXY-2020-011-08"],"award-info":[{"award-number":["CXY-2020-011-08"]}]},{"name":"Science technology plan of ShaanXi","award":["FRGS\/1\/2022\/STG07\/UM\/02\/6"],"award-info":[{"award-number":["FRGS\/1\/2022\/STG07\/UM\/02\/6"]}]},{"name":"Science technology plan of Yulin City","award":["2020GY-187"],"award-info":[{"award-number":["2020GY-187"]}]},{"name":"Science technology plan of Yulin City","award":["CXY-2020-011-08"],"award-info":[{"award-number":["CXY-2020-011-08"]}]},{"name":"Science technology plan of Yulin City","award":["FRGS\/1\/2022\/STG07\/UM\/02\/6"],"award-info":[{"award-number":["FRGS\/1\/2022\/STG07\/UM\/02\/6"]}]},{"name":"Fundamental Research Grant Scheme, Ministry of Education Malaysia","award":["2020GY-187"],"award-info":[{"award-number":["2020GY-187"]}]},{"name":"Fundamental Research Grant Scheme, Ministry of Education Malaysia","award":["CXY-2020-011-08"],"award-info":[{"award-number":["CXY-2020-011-08"]}]},{"name":"Fundamental Research Grant Scheme, Ministry of Education Malaysia","award":["FRGS\/1\/2022\/STG07\/UM\/02\/6"],"award-info":[{"award-number":["FRGS\/1\/2022\/STG07\/UM\/02\/6"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, we proposed a sensitivity-enhanced temperature sensor, a compact harmonic Vernier sensor based on an in-fiber Fabry\u2013Perot Interferometer (FPI), with three reflective interfaces for the measurement of gas temperature and pressure. FPI consists of air and silica cavities formulated by single-mode optical fiber (SMF) and several short hollow core fiber segments. One of the cavity lengths is deliberately made larger to excite several harmonics of the Vernier effect that have different sensitivity magnifications to the gas pressure and temperature. The spectral curve could be demodulated using a digital bandpass filter to extract the interference spectrum according to the spatial frequencies of resonance cavities. The findings indicate that the material and structural properties of the resonance cavities have an impact on the respective temperature sensitivity and pressure sensitivity. The measured pressure sensitivity and temperature sensitivity of the proposed sensor are 114 nm\/MPa and 176 pm\/\u00b0C, respectively. Therefore, the proposed sensor combines ease of fabrication and high sensitivity, making it great potential for practical sensing measurements.<\/jats:p>","DOI":"10.3390\/s23084142","type":"journal-article","created":{"date-parts":[[2023,4,21]],"date-time":"2023-04-21T02:05:31Z","timestamp":1682042731000},"page":"4142","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Compact Harmonic Vernier Sensor Based on an In-Fiber FPI with Three Reflector System for Simultaneous Gas Pressure and Temperature Measurement"],"prefix":"10.3390","volume":"23","author":[{"given":"Jinxiao","family":"Dan","sequence":"first","affiliation":[{"name":"School of Physics, Northwest University, Xi\u2019an 710069, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenjie","family":"Dang","sequence":"additional","affiliation":[{"name":"School of Physics, Northwest University, Xi\u2019an 710069, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zeren","family":"Li","sequence":"additional","affiliation":[{"name":"School of Physics, Northwest University, Xi\u2019an 710069, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5679-1444","authenticated-orcid":false,"given":"Pengyu","family":"Nan","sequence":"additional","affiliation":[{"name":"School of Physics, Northwest University, Xi\u2019an 710069, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guoguo","family":"Xin","sequence":"additional","affiliation":[{"name":"School of Physics, Northwest University, Xi\u2019an 710069, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kok-Sing","family":"Lim","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Harith","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, University Malaya, Kuala Lumpur 50603, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hangzhou","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Physics, Northwest University, Xi\u2019an 710069, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,4,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"114835","DOI":"10.1016\/j.engstruct.2022.114835","article-title":"Pressure test of a prestressed concrete cylinder pipe using distributed fiber optic sensors: Instrumentation and results","volume":"270","author":"Li","year":"2022","journal-title":"Eng. Struct."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"106508","DOI":"10.1016\/j.optlaseng.2020.106508","article-title":"Fiber Optic Shape Sensors: A comprehensive review","volume":"139","author":"Floris","year":"2021","journal-title":"Opt. Lasers Eng."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2415","DOI":"10.1364\/JOSAB.460139","article-title":"Optimized design of an ultrasensitive tapered dual-hole fiber gas pressure sensor operating near the dispersion turning point","volume":"39","author":"Wang","year":"2022","journal-title":"J. Opt. Soc. Am. B"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"103498","DOI":"10.1016\/j.cryogenics.2022.103498","article-title":"Refractometric and temperature sensors based on one-dimensional binary photonic crystal including a superconducting layer","volume":"125","author":"Almawgani","year":"2022","journal-title":"Cryogenics"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1716","DOI":"10.1364\/JOSAB.461472","article-title":"Pressure sensor based on multiple Fano resonance in metal\u2013insulator\u2013metal waveguide coupled resonator structure","volume":"39","author":"Chen","year":"2022","journal-title":"J. Opt. Soc. Am. B"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"18666","DOI":"10.3390\/s150818666","article-title":"Fibre Optic Sensors for Structural Health Monitoring of Aircraft Composite Structures: Recent Advances and Applications","volume":"15","year":"2015","journal-title":"Sensors"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.snb.2014.03.071","article-title":"Temperature-insensitive refractive index sensor based on in-fiber Michelson interferometer","volume":"199","author":"Li","year":"2014","journal-title":"Sens. Actuators B Chem."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1177\/1475921719850641","article-title":"A stretchable and large-scale guided wave sensor network for aircraft smart skin of structural health monitoring","volume":"20","author":"Wang","year":"2019","journal-title":"Struct. Health Monit."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"107998","DOI":"10.1016\/j.optlastec.2022.107998","article-title":"An ultra-sensitive gas pressure sensor based on tapered fiber coated with PDMS film working at TAP","volume":"151","author":"Zhao","year":"2022","journal-title":"Opt. Laser Technol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"e2307","DOI":"10.1002\/stc.2307","article-title":"Fibre Bragg grating sensor-based damage response monitoring of an asymmetric reinforced concrete shear wall structure subjected to progressive seismic loads","volume":"26","author":"Zhang","year":"2019","journal-title":"Struct. Control Health Monit."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1007\/s13320-017-0419-z","article-title":"Review on pressure sensors for structural health monitoring","volume":"7","author":"Sikarwar","year":"2017","journal-title":"Photonic Sens."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"3665","DOI":"10.1364\/OE.451764","article-title":"All-sapphire fiber-optic pressure sensors for extreme harsh environments","volume":"30","author":"Shao","year":"2022","journal-title":"Opt. Express"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2467","DOI":"10.3390\/s120302467","article-title":"Interferometric fiber optic sensors","volume":"12","author":"Lee","year":"2012","journal-title":"Sensors"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"110705","DOI":"10.1016\/j.measurement.2022.110705","article-title":"Multiparameter measuring system using fiber optic sensors for hydraulic temperature, pressure and flow monitoring","volume":"190","author":"Liu","year":"2022","journal-title":"Measurement"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"4891","DOI":"10.1364\/OL.40.004891","article-title":"Ultra-high sensitivity Fabry-Perot interferometer gas refractive index fiber sensor based on photonic crystal fiber and Vernier effect","volume":"40","author":"Quan","year":"2015","journal-title":"Opt. Lett."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"14483","DOI":"10.1364\/OE.25.014483","article-title":"Hybrid Fabry-Perot interferometer for simultaneous liquid refractive index and temperature measurement","volume":"25","author":"Xu","year":"2017","journal-title":"Opt. Express"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1738","DOI":"10.1364\/AO.57.001738","article-title":"Microbubble-based fiber-optic Fabry-Perot pressure sensor for high-temperature application","volume":"57","author":"Li","year":"2018","journal-title":"Appl. Opt."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"111589","DOI":"10.1016\/j.sna.2019.111589","article-title":"Temperature insensitive air-cavity Fabry-Perot gas pressure sensor based on core-offset fusion of hollow-core fibers","volume":"298","author":"Chen","year":"2019","journal-title":"Sens. Actuators A Phys."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Liang, H., Jia, P., Liu, J., Fang, G., Li, Z., Hong, Y., Liang, T., and Xiong, J. (2018). Diaphragm-Free Fiber-Optic Fabry-Perot Interferometric Gas Pressure Sensor for High Temperature Application. Sensors, 18.","DOI":"10.3390\/s18041011"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"23817","DOI":"10.1364\/OE.17.023817","article-title":"Highly sensitive digital optical sensor based on cascaded high-Q ring-resonators","volume":"17","author":"Dai","year":"2009","journal-title":"Opt. Express"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"156","DOI":"10.1016\/j.optcom.2010.08.035","article-title":"Highly-sensitive silicon-on-insulator sensor based on two cascaded micro-ring resonators with vernier effect","volume":"284","author":"Jin","year":"2011","journal-title":"Opt. Commun."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"103160","DOI":"10.1016\/j.yofte.2022.103160","article-title":"High-sensitivity gas pressure sensor with low temperature cross-talk based on Vernier effect of cascaded Fabry-Perot interferometers","volume":"75","author":"Tian","year":"2023","journal-title":"Opt. Fiber Technol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"108451","DOI":"10.1016\/j.measurement.2020.108451","article-title":"Fiber-optic sensors based on Vernier effect","volume":"167","author":"Liu","year":"2021","journal-title":"Measurement"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Gomes, A.D., Ferreira, M.S., Bierlich, J., Kobelke, J., Rothhardt, M., Bartelt, H., and Fraz\u00e3o, O. (2019). Optical Harmonic Vernier Effect: A New Tool for High Performance Interferometric Fiber Sensors. Sensors, 19.","DOI":"10.3390\/s19245431"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"106198","DOI":"10.1016\/j.optlastec.2020.106198","article-title":"Hollow microsphere combined with optical harmonic Vernier effect for strain and temperature discrimination","volume":"127","author":"Gomes","year":"2020","journal-title":"Opt. Laser Technol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"107007","DOI":"10.1016\/j.optlastec.2021.107007","article-title":"Simplified highly-sensitive gas pressure sensor based on harmonic Vernier effect","volume":"140","author":"Yang","year":"2021","journal-title":"Opt. Laser Technol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"108532","DOI":"10.1016\/j.optlastec.2022.108532","article-title":"Ultrasensitive fiber-based gas pressure sensor based on harmonic Vernier effect with enhanced contrast","volume":"156","author":"Luo","year":"2022","journal-title":"Opt. Laser Technol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"109029","DOI":"10.1016\/j.optlastec.2022.109029","article-title":"Sensitivity enhanced fiber optic temperature sensor based on optical carrier microwave photonic interferometry with harmonic Vernier effect","volume":"160","author":"Chen","year":"2023","journal-title":"Opt. Laser Technol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1504","DOI":"10.1109\/JLT.2020.3038238","article-title":"Ultrasensitive Strain Sensing by Using Two Parallel Structured Fabry--Perot Interferometers in Cascaded Connection","volume":"39","author":"Wang","year":"2021","journal-title":"J. Light. Technol."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"127173","DOI":"10.1016\/j.optcom.2021.127173","article-title":"A sensitivity-enhanced temperature sensor with end-coated PDMS in few mode fiber based on vernier effect","volume":"497","author":"Fu","year":"2021","journal-title":"Opt. Commun."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"166","DOI":"10.1016\/j.optcom.2017.12.012","article-title":"Optical cascaded Fabry\u2013Perot interferometer hydrogen sensor based on vernier effect","volume":"414","author":"Li","year":"2018","journal-title":"Opt. Commun."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1016\/j.yofte.2018.09.021","article-title":"Simultaneous measurement of gas pressure and temperature with integrated optical fiber FPI sensor based on in-fiber micro-cavity and fiber-tip","volume":"46","author":"Liu","year":"2018","journal-title":"Opt. Fiber Technol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"102027","DOI":"10.1016\/j.yofte.2019.102027","article-title":"Discriminative measurement for temperature and humidity using hollow-core Fabry-Perot interferometer","volume":"53","author":"He","year":"2019","journal-title":"Opt. Fiber Technol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"3444","DOI":"10.1109\/JLT.2019.2917062","article-title":"High-Sensitivity Gas Pressure Fabry\u2013Perot Fiber Probe With Micro-Channel Based on Vernier Effect","volume":"37","author":"Li","year":"2019","journal-title":"J. Light. Technol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"166956","DOI":"10.1016\/j.ijleo.2021.166956","article-title":"Hypersensitive high-temperature gas pressure sensor with Vernier effect by two parallel Fabry-Perot interferometers","volume":"241","author":"Han","year":"2021","journal-title":"Optik"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/8\/4142\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:20:06Z","timestamp":1760124006000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/8\/4142"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,4,20]]},"references-count":35,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2023,4]]}},"alternative-id":["s23084142"],"URL":"https:\/\/doi.org\/10.3390\/s23084142","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,4,20]]}}}