修饰不同金纳米颗粒的极大角倾斜光纤光栅折射率传感特性研究

Study on Refractive Index Sensing Properties of Excessively Tilted Fiber Grating Modified by Different Gold Nanoparticles

摘要:

研究了分别使用大尺寸金纳米壳与星型金纳米颗粒修饰极大角倾斜光纤光栅(ExTFG)的局域表面等离子体共振(LSPR)传感器,实验对比了这两种ExTFG-LSPR传感器的折射率传感特性。实验结果表明:修饰星型金纳米颗粒的ExTFG传感器,其TM、TE模的基于波长变化的折射率灵敏度分别提升约15.52和12.8nm/RIU,但共振吸收效应不明显；而修饰大尺寸金纳米壳的ExTFG传感器,在大尺寸金纳米壳的LSPR作用下,其TM、TE模的基于波长变化的折射率灵敏度分别提升约31.1和26.99nm/RIU,同时,TM与TE模在C-L波段表现出强烈的共振吸收,基于归一化强度变化的折射率灵敏度分别约为185.18%/RIU和251.83%/RIU。

Abstract:

Proposed is a kind of localized surface plasmon resonance (LSPR) sensor based on excessively tilted fiber grating (ExTFG) modified by large-scale gold nanoshells and star-shaped gold nanoparticles, respectively. The refractive index sensing characteristics of the two kinds of ExTFG-LSPR sensors were studied. Experimental results show that the wavelength-based RI sensitivity of the TM and TE mode of ExTFG sensor modified by star-shaped nanoparticles is improved by about 15.52 and 12.8nm/RIU, respectively, but the resonance absorption effect is not obvious; while for the Ex-TFG modified by large-scale gold nanoshells, the wavelength-based RI sensitivity of TM and TE modes is improved by about 31.1 and 26.99nm/RIU, respectively, due to the effect of LSPR of large-size gold nanoshells, and the intensity-based RI sensitivity of the TM and TE modes is about 185.18%/RIU and 251.83%/RIU, respectively.