Hailong Du's research while affiliated with Zhengzhou University and other places

In order to achieve low refractive index detection in biomedical and material chemistry, a D-type microstructured optical fiber (MOF) sensor based on surface plasmon resonance (SPR) is proposed in this paper. The sensor uses gold nanofilm as sensing material between the core of the fiber and the plasma on the surface, and is coated at the open ring. Parametric analysis of the open-ring diameter, air hole diameter, and thickness of the gold nanofilm of the sensor was carried out by finite element method. The simulation results show that the sensor has a wavelength sensitivity of up to 10,900 nm/RIU, the refractive index range of 1.20–1.34, optimal resolution of 9.17 × 10⁻⁶ RIU, and a decent figure of merit (FOM) is 46.2 RIU⁻¹. The proposed MOF-SPR sensor has high wavelength sensitivity and low resolution in a similar detection range compared to existing studies. The sensor is capable of detecting not only low refractive index substances, such as liquid medical oxygen with a refractive index of 1.22 and sevoflurane with a refractive index of 1.27, but also conventional refractive index substances such as water contamination with a refractive index near 1.33, providing a wide detection range. Therefore, the sensor is competitive in the detection of some low refractive index material detection fields.

In order to achieve low refractive index detection in biomedical and material chemistry, a D-type microstructured optical fiber (MOF) sensor based on surface plasmon resonance (SPR) is proposed in this paper. The sensor uses gold nanofilm as sensing material between the core of the fiber and the plasma on the surface, and is coated at the open-ring. Parametric analysis of the open-ring diameter, air hole diameter and thickness of the gold nanofilm of the sensor was carried out by finite element method. The simulation results show that the sensor has a wavelength sensitivity of up to 10900 nm/RIU, the refractive index range of 1.20–1.34, optimal resolution of 9.17×10 − 6 RIU, and a decent figure of merit (FOM) is 46.2 RIU − 1 . The proposed MOF-SPR sensor has high wavelength sensitivity and low resolution in a similar detection range compared to existing studies. The sensor is capable of detecting not only low refractive index substances, such as liquid medical oxygen with a refractive index of 1.22 and sevoflurane with a refractive index of 1.27, but also conventional refractive index substances such as water contamination with a refractive index near 1.33, providing a wide detection range. Therefore, the sensor is competitive in the detection of some low refractive index material detection fields.

In this paper, a dual-core microchannel-based fiber sensor is studied by using finite element method in the visible and near-infrared bands. Plasmonic material gold (Au) is deposited in microchannel to generate the surface plasmon resonance (SPR) effect, so that sensor can detect the change in RI of its surrounding analyte. Simulation results show that the maximum wavelength sensitivity and resolution are 33600 nm/RIU and 2.97 × 10⁻⁶RIU for y polarization in the RI range of 1.33 to 1.44, respectively. The highest figure of merit (FOM) of the sensor is 961 for y polarization. In addition, we study the effects brought by the structural changes of the fiber sensor, and the results show that the design of “microchannel coating” dramatically improves the refractive index (RI) detection ability of the sensor. The D-shaped dual-core microchannel-based photonic crystal fiber sensor proposed in this paper has a simple structure, low manufacturing complexity, and high sensitivity. Combined with external sensing technology, this sensor has great application potential in the fields of biotechnology, medical diagnosis, and environmental protection.