Transducer based on surface plasmon resonance with thermal modification of metal layer properties

In this work, a surface plasmon resonance (SPR) sensor based on a novel liquid-core polymer optical fiber (POF) is proposed and numerically analyzed for refractive index (RI) detection. The polytetrafluoroethylene (PTFE) fiber is selected as the platform for SPR sensing. We combine the PTFE-based POF with the liquid-core structure by introducing a hole filled with analyte into the fiber center. The hole also acts as the fiber core to guide the incident light. This design helps to realize the detection of solutions with low RI values (around 1.33), while keeping the distinguished sensing characteristics of the liquid-core structure. Two side air holes are introduced into the cladding and a thin silver film protected by a titanium dioxide layer is plated on the wall of one air hole, which helps to control the mode coupling. In order to optimize the design of this sensor, the impacts of parameters such as metal layer thicknesses and the central hole radius are investigated using the full-vector finite element method (FEM). After optimization, our design shows a wavelength interrogation sensitivity reaching up to 16,750 nm/RIU and an average full-width at half-maximum (FWHM) of 42.86 nm in the RI range of 1.325–1.35.

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Study of Computational Theory of Surface Plasmon Resonance (SPR) for Porcine Gelatin Detected Sensor Based Nanomaterial Fe3O4–CNT in Otto’s Configuration

Proceeding International Conference on Science and Engineering ◽

10.14421/icse.v1.279 ◽

2017 ◽

Vol 1 ◽

pp. 115-124

Author(s):

Maulina Lutfiyah ◽

Asih Melati

Keyword(s):

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Laser Light ◽

Metal Layer ◽

Biomolecular Detection ◽

Computational Theory ◽

Gelatin Layer ◽

Detection Of Biomolecules ◽

Angular Shift

Accurate biomolecular detection can be performed through the Surface Plasmon Resonance (SPR) phenomenon. This study was conducted to determine the effect of the addition of Fe3O4 and Carbon Nanotube (CNT) nanomaterials in the Otto configurations and their use as porcine detection sensors. The research was conducted theoretically by finding the equation of reflectance and computationally using Matlab software version 7.12.0 to know SPR angle and reflectance value. This research uses ATR method with Otto configuration. The modeling was finished using HeNe laser light on 632.8 nm wavelength, semi-circle prism type BK7, metal layer of gold nanoparticles. The results of the research can be used in the detection of porcine gelatin by Otto configurations. The best air gap thickness is 30 nm. The best thickness of the gold layer and Fe3O4 layer are 50 nm and 0.05 nm. The applied of MWCNT nanoparticles is not effective in the detection of biomolecules based SPR. While the thickness of SWCNT used is 1 nm. The SWCNT material also proved to be better used in SPR systems. The addition of porcine gelatin layer in the system shows a graphic change in the form of increasing reflectance value and SPR angular shift.

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Thin Film Thickness Measurement by Surface Plasmon Resonance Using a Modified Otto’s Configuration Combined with Ellipsometry

International Journal of Automation Technology ◽

10.20965/ijat.2011.p0236 ◽

2011 ◽

Vol 5 (2) ◽

pp. 236-240 ◽

Cited By ~ 3

Author(s):

Yasuhiro Mizutani ◽

◽

Tetsuo Iwata

Keyword(s):

Thin Film ◽

Surface Plasmon Resonance ◽

Film Thickness ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Dielectric Material ◽

Metal Layer ◽

Sample Surface ◽

Adjustment Process ◽

Thin Film Thickness

We have developed a method of measuring thin film thickness by using two optical properties that are highsensitivity for a film thickness, such as surface plasmon resonance (SPR) and elliptical properties with SPR response. The SPR signal is high sensitivity, suitable for measuring the thickness of a sample with a thin layer. This phenomenon can be detected by measuring the absorbance on the sample surface. We focused on the Otto configuration, a famous method for the generation of a SPR signal, which consists of 4 layers such as a SiO2 substrate, air, dielectric material and a metal layer. It is useful for the measurement of thin film thickness because there is an air layer in the configuration. However, the configuration has the disadvantage: it is necessary to adjust the distance from sample surface to the SiO2 substrate on a nanometer order. To overcome the problem, we focused on the modified Otto’s configuration proposed by Bliokh et. al [Appl. Phys. Lett. 89, 021908 (2006)]. In the configuration, there is a plano-convex lens of SiO2 as the substrate. By using its curvature, there is no adjustment process and the SPR signal can be detected easily. The SPR signal has a polarization property that depends on the thin film thickness. By analyzing of polarization properties of the SPR signal by means of ellipsometry, thin film thickness can be measured with sub-nanometer accuracy which is higher than the SPR signals. In this paper, further results involving the measurement are presented and discussed.

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