TY - JOUR
T1 - Sensitivity enhancement of gold nanospheres assisted CO2 laser tapered optical fiber for refractive index sensor
AU - Hidayat, Nurul
AU - Safwan Abd Aziz, Muhammad
AU - Nur, Hadi
AU - Taufiq, Ahmad
AU - Mufti, Nandang
AU - Rakhmata Mukti, Rino
AU - Bakhtiar, Hazri
N1 - Publisher Copyright:
© 2023 Elsevier Inc.
PY - 2023/5
Y1 - 2023/5
N2 - Tapered optical fibers (TOFs) have been intensively used as sensors due to their high sensitivity, simple structure, and excellent coupling efficiency. In this paper, we reported the successful rapid tapering of single mode and multimode fibers using CO2 laser beam at working wavelength of 10.6 μm. Clean and symmetric tapers could be produced in just 5 s using this method. Arduino-based microcontroller was included in the tapering set-up to precisely control the fiber pulling speed and distance. Smaller waist diameters that were observed in multimode than in single mode fibers generated more evanescent waves on the cladding of tapered multimode fibers (TMMFs). This implied that TMMFs performed better refractive index (RI) sensitivity, within the range of 1.3325–1.4266, than tapered single mode fibers (TSMFs). Furthermore, localized surface plasmon resonance (LSPR) effect was coupled with evanescent wave through AuNSs immobilization on the TOF surface. The AuNSs having average particle diameter of 12.70 nm was synthesized by citrate reduction route. The formation of AuNSs was confirmed by (ultraviolet–visible) UV–vis and high-resolution transmission electron microscopy (HRTEM) data. Self-assembly monolayer approach was conducted to immobilize AuNSs on the 3-mercaptopropyl trimethoxysilane (MPTMS)-functionalized surface of the TOFs. The AuNSs immobilization on TMMFs could improve the sensitivity up to 122 %. Besides sensitive to RI changes, the sensors were also excellent in terms of repeatability and reversibility performances. Finally, this paper described the amplitude modality-based RI sensing mechanism due to evanescent wave and LSPR effects.
AB - Tapered optical fibers (TOFs) have been intensively used as sensors due to their high sensitivity, simple structure, and excellent coupling efficiency. In this paper, we reported the successful rapid tapering of single mode and multimode fibers using CO2 laser beam at working wavelength of 10.6 μm. Clean and symmetric tapers could be produced in just 5 s using this method. Arduino-based microcontroller was included in the tapering set-up to precisely control the fiber pulling speed and distance. Smaller waist diameters that were observed in multimode than in single mode fibers generated more evanescent waves on the cladding of tapered multimode fibers (TMMFs). This implied that TMMFs performed better refractive index (RI) sensitivity, within the range of 1.3325–1.4266, than tapered single mode fibers (TSMFs). Furthermore, localized surface plasmon resonance (LSPR) effect was coupled with evanescent wave through AuNSs immobilization on the TOF surface. The AuNSs having average particle diameter of 12.70 nm was synthesized by citrate reduction route. The formation of AuNSs was confirmed by (ultraviolet–visible) UV–vis and high-resolution transmission electron microscopy (HRTEM) data. Self-assembly monolayer approach was conducted to immobilize AuNSs on the 3-mercaptopropyl trimethoxysilane (MPTMS)-functionalized surface of the TOFs. The AuNSs immobilization on TMMFs could improve the sensitivity up to 122 %. Besides sensitive to RI changes, the sensors were also excellent in terms of repeatability and reversibility performances. Finally, this paper described the amplitude modality-based RI sensing mechanism due to evanescent wave and LSPR effects.
KW - CO laser
KW - Evanescent wave
KW - Gold nanosphere
KW - Localized surface plasmon resonance
KW - Refractive index sensing
KW - Tapered optical fiber
UR - http://www.scopus.com/inward/record.url?scp=85147856781&partnerID=8YFLogxK
U2 - 10.1016/j.yofte.2023.103275
DO - 10.1016/j.yofte.2023.103275
M3 - Article
AN - SCOPUS:85147856781
SN - 1068-5200
VL - 77
JO - Optical Fiber Technology
JF - Optical Fiber Technology
M1 - 103275
ER -