Wang Fengmin, Wei Yong, Han Yanhong
Liren College, Yanshan University, Qinhuangdao 066004, China.
School of Information Science and Engineering, Yanshan University, Qinhuangdao 066004, China.
Sensors (Basel). 2023 Jul 23;23(14):6617. doi: 10.3390/s23146617.
In order to detect the refractive index (RI) of high refractive index materials such as trichlorobenzene and aniline in the near-infrared and mid-infrared spectra and expand the detection range of the refractive index, a surface plasmon resonance (SPR) photonic crystal fiber (PCF) sensor based on an elliptical sensing channel is proposed for high refractive index detection. The fiber core and the analyte channel are surrounded by two types of air holes with different sizes. When the surface plasmon resonance effect appears at the interface between the fiber core and the elliptical sensing layer, obvious resonance peaks appear in the near-infrared and mid-infrared bands. The full vector finite element method (FEM) is used to study the sensing characteristics of the sensor and the influence of structural parameters on the resonance peak. The results demonstrate that the sensor achieves detection in the refractive index range of 1.41-1.58, in the wavelength range of 1600-3200 nm. The average wavelength sensitivity is 9217.22 nm/RIU, and the refractive index resolution is 10.85 × 10 RIU. The proposed sensor realizes high refractive index detection in the near-infrared and mid-infrared bands, and obtains an ultra-wide detection range and higher sensitivity. The sensor has broad application prospects in chemical detection, biomedical sensing and other fields, and provides a theoretical reference for the design of a photonic crystal fiber surface plasmon resonance sensor.
为了检测三氯苯和苯胺等高折射率材料在近红外和中红外光谱中的折射率（RI），并扩大折射率的检测范围，提出了一种基于椭圆传感通道的表面等离子体共振（SPR）光子晶体光纤（PCF）传感器用于高折射率检测。光纤纤芯和分析物通道被两种不同尺寸的气孔包围。当在光纤纤芯与椭圆传感层的界面处出现表面等离子体共振效应时，在近红外和中红外波段会出现明显的共振峰。采用全矢量有限元法（FEM）研究了该传感器的传感特性以及结构参数对共振峰的影响。结果表明，该传感器在1600 - 3200 nm波长范围内实现了1.41 - 1.58折射率范围的检测。平均波长灵敏度为9217.22 nm/RIU，折射率分辨率为10.85×10 RIU。所提出的传感器实现了近红外和中红外波段的高折射率检测，并获得了超宽的检测范围和更高的灵敏度。该传感器在化学检测、生物医学传感等领域具有广阔的应用前景，为光子晶体光纤表面等离子体共振传感器的设计提供了理论参考。
