Micro-Lab on Tip: High-Performance Dual-Channel Surface Plasmon Resonance Sensor Integrated on Fiber-Optic End Facet

• Published in: Sensors and actuators. B, Chemical Vol. 351; p. 130978
• Main Authors: Kong, Ling-Xin, Chi, Meng-Jiao, Ren, Cheng, Ni, Li-Fa, Li, Zhe, Zhang, Yun-Shan
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.01.2022; Elsevier Science Ltd
• Subjects: Fiber optics; Humidity; Humidity measurement; Optical fiber sensor; Optical fibers; Optics; Parameters; Polydimethylsiloxane; Polyvinyl alcohol; Refractive index; Refractivity; Sensitivity; Surface plasmon resonance; Temperature; Temperature measurement; Titanium dioxide; Temperature; Surface plasmon resonance; Optical fiber sensor; Refractive index; Humidity
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2021.130978

It is a challenging and valuable work to realize the simultaneous sensing of two or more parameters at the end of optical fiber. In this paper, we implemented an ultra compact dual-channel surface plasmon resonance (SPR) sensor on fiber-optic end facet. A dual-layer polymer microcap based on different refractive index (RI) films was used to segment a single Cu/TiO2 coated micro-cone on single mode fiber (SMF) end facet for producing a sensing spectrum with two separated SPR dips. The SPR dip (channel-II) generated by Polydimethylsiloxane (PDMS) microcap can reach high sensitivity temperature measurement of 2.935 nm/°C in the range of 30–70 °C, and the SPR dip (channel-I) generated by polyvinyl alcohol (PVA) microcap can achieve high sensitivity humidity measurement of 1.08 nm/%RH in the range of 20%RH-70%RH. Finally, the simultaneous detection of humidity and temperature can be realized by the matrix established by channel-I and channel-II. This is a simple, effective and reproducible micro laboratory on optical fiber end facet for dual parameter sensing. •An ultra compact dual channel SPR micro-cone sensor on the flat end facet of SMF is proposed.•The fabrication process is simple and reproducible.•The channel-II can reach 2.935 nm/°C, and the channel-I can achieve 1.08 nm/%RH.•The temperature crosstalk of channel-I can be compensated by Channel-II.•The structure can be easily extended to the measurement of other biochemical parameters.