Dielectric nano-imprint lithography-sol-gel nanostructured for high-sensitivity refractive index sensing

In this paper, a novel and cost-effective photonic platform based on silica–titania material is discussed. The silica–titania thin films were grown utilizing the sol–gel dip-coating method and characterized with the help of the prism-insertion technique. Afterwards, the mode sensitivity analysis of the silica–titania ridge waveguide is investigated via the finite element method. Silica–titania waveguide systems are highly attractive due to their ease of development, low fabrication cost, low propagation losses and operation in both visible and near-infrared wavelength ranges. Finally, a ring resonator (RR) sensor device was modelled for refractive index sensing applications, offering a sensitivity of 230 nm/RIU, a figure of merit (FOM) of 418.2 RIU−1, and Q-factor of 2247.5 at the improved geometric parameters. We believe that the abovementioned integrated photonics platform is highly suitable for high-performance and economically reasonable optical sensing devices.

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High-sensitivity complex refractive index sensing based on Fano resonance in the subwavelength grating waveguide micro-ring resonator

Optics Express ◽

10.1364/oe.25.020911 ◽

2017 ◽

Vol 25 (17) ◽

pp. 20911 ◽

Cited By ~ 30

Author(s):

Zhengrui Tu ◽

Dingshan Gao ◽

Meiling Zhang ◽

Daming Zhang

Keyword(s):

Refractive Index ◽

Fano Resonance ◽

Ring Resonator ◽

Complex Refractive Index ◽

High Sensitivity ◽

Subwavelength Grating ◽

Refractive Index Sensing

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Refractive Index Sensing through Surface Plasmon Resonance in Light-Diffusing Fibers

Applied Sciences ◽

10.3390/app8071172 ◽

2018 ◽

Vol 8 (7) ◽

pp. 1172 ◽

Cited By ~ 11

Author(s):

Nunzio Cennamo ◽

Luigi Zeni ◽

Ester Catalano ◽

Francesco Arcadio ◽

Aldo Minardo

Keyword(s):

Refractive Index ◽

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Optical Fiber Sensor ◽

Fiber Surface ◽

High Sensitivity ◽

Refractive Index Sensing ◽

Sensor Platform ◽

Chemical Procedure

In this paper, we show that light-diffusing fibers (LDF) can be efficiently used as host material for surface plasmon resonance (SPR)-based refractive index sensing. This novel platform does not require a chemical procedure to remove the cladding or enhance the evanescent field, which is expected to give better reproducibility of the sensing interface. The SPR sensor has been realized by first removing the cladding with a simple mechanical stripper, and then covering the unclad fiber surface with a thin gold film. The tests have been carried out using water–glycerin mixtures with refractive indices ranging from 1.332 to 1.394. The experimental results reveal a high sensitivity of the SPR wavelength to the outer medium’s refractive index, with values ranging from ~1500 to ~4000 nm/RIU in the analyzed range. The results suggest that the proposed optical fiber sensor platform could be used in biochemical applications.

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