{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T15:09:45Z","timestamp":1781708985924,"version":"3.54.5"},"reference-count":34,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,10,24]],"date-time":"2020-10-24T00:00:00Z","timestamp":1603497600000},"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>In this work, a highly sensitive dual-core configured microchannel-based plasmonic refractive index (RI) sensor was investigated, which can be used for low RI detection. Both the sensing layer and the plasmonic material layer were built outside of the fiber design to detect the surrounding medium\u2019s RI changes. Additionally, the effects of different plasmonic materials gold (Au), silver (Ag), and copper (Cu) toward sensitivity were investigated for the same structure. An adhesive agent was used in this work, titanium dioxide (TiO2), and was coated on top of the plasmonic material to prevent the oxidation of Ag and Cu. The coupling strength between the fundamental mode and the surface plasmon polariton (SPP) mode was observed to be very strong due to the TiO2 adhesive agent. With a resolution of 7.41 \u00d7 10\u22127 RIU, maximum wavelength sensitivity (WS) of 135,000 nm\/RIU and amplitude sensitivity (AS) of 3239 RIU\u22121 were achieved using the proposed sensor while using Au as a plasmonic material for an analyte RI range of 1.29\u20131.39. A detailed study of relevant literature revealed that the achieved wavelength sensitivity for plasmonic material gold (Au) is the highest among reported photonic crystal fiber (PCF)-surface plasmon resonance (SPR) sensors to date.<\/jats:p>","DOI":"10.3390\/s20216049","type":"journal-article","created":{"date-parts":[[2020,10,26]],"date-time":"2020-10-26T03:51:47Z","timestamp":1603684307000},"page":"6049","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Sensitivity Enhancement of Modified D-Shaped Microchannel PCF-Based Surface Plasmon Resonance Sensor"],"prefix":"10.3390","volume":"20","author":[{"given":"Abdullah Al","family":"Noman","sequence":"first","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Independent University Bangaldesh, Dhaka 1229, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emranul","family":"Haque","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Independent University Bangaldesh, Dhaka 1229, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8215-780X","authenticated-orcid":false,"given":"Md. Anwar","family":"Hossain","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Bangladesh University of Business and Technology (BUBT), Dhaka 1216, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nguyen Hoang","family":"Hai","sequence":"additional","affiliation":[{"name":"School of Electronics and Telecommunication, Hanoi University of Science and Technology, Ha Noi 10000, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoshinori","family":"Namihira","sequence":"additional","affiliation":[{"name":"Faculty of Engineering, University of the Ryukyus, Okinawa 903-0213, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8225-9969","authenticated-orcid":false,"given":"Feroz","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Independent University Bangaldesh, Dhaka 1229, Bangladesh"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"409","DOI":"10.1038\/nphoton.2012.161","article-title":"Plasmonics in the mid-infrared","volume":"6","author":"Stanley","year":"2012","journal-title":"Nat. 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