High-sensitivity coreless fiber surface plasmon resonance refractive index sensor based on Au/TiO2

Fiber optic surface plasmon resonance sensor (SPR) play an important role in various fields where highly sensitive sensors are suitable. In this paper, we propose an SPR refractive index sensor composed of multi-mode fiber-coreless fiber-multimode fiber (MCM) structure modified by Au/TiO2 nanofiber material. The experimental results show that the sensitivity of the TiO2 nanofiber/Au structure sensor is 3687.65 nm/RIU and the quality factor is as high as 29.50 in the refractive index range of 1.333-1.380, which is 2.05 times that of the Au film structure sensor. Such a new structure optimizes a variety of properties and can be widely used in chemical sensing, safety detection, small molecule measurement, medical sensing, and high-sensitivity sensing.