基于空气孔微结构光纤的表面等离子体共振折射率传感器北大核心CSCD

提出了一种基于表面等离子体共振(SPR)效应增强的光子晶体光纤折射率传感器。该传感器结构通过光纤熔接机拼接光子晶体光纤(PCF),在光子晶体光纤中间引入一个空气孔形成PCF-空气孔-PCF的光纤传感结构,随后使用磁控溅射镀膜工艺在其表面沉积一层薄金膜制备而成。实验探究了折射率及温度对传感器的响应。结果表明,在1.333~1.389的折射率范围内,所提出的传感器的平均折射率灵敏度为2 142.52 nm,且测量线性度为0.981,品质因子约13.10。实验结果表明该传感器对温度不敏感。相比于无空气孔的PCF传感结构,引入的空气孔增强了SPR效应,使得传感器拥有良好的共振峰深度。得益于上述优势,该类型传感器有望在生物医学、环境监测等领域得到应用。

Surface plasmon resonance refractive index sensor based on microstructured fiber with air-hole

A photonic crystal fiber refractive index (RI) sensor based on enhanced surface plasmon resonance (SPR) effect is proposed. The sensor structure is spliced with a photonic crystal fiber (PCF) by a fiber fusion splicer, so that an air hole is introduced in the middle of the photonic crystal fiber to form a PCF-air hole-PCF optical fiber sensing structure. Then, a thin gold film is deposited on its surface by using magnetron sputtering coating process. Experiments are carried out to investigate the response of the refractive index and temperature of the sensor. The results show that in the refractive index (RI) range of 1.333?1.389, the sensor has an average RI sensitivity of 2 142.52 nm, with a linearity of 0.981 and a quality factor about 13.10. Experimental results show that the sensor is not sensitive to temperature. Compared with the PCF sensing structure without air hole, the air hole introduced enhances the SPR effect, so that the sensor has a good resonance peak depth. Benefiting from the above advantages, this type of sensor is expected to be applied in fields such as biomedicine and environmental monitoring.