Theoretical research on a late-model multistage refractive index sensor based on photonic spin Hall effect.

In this paper, a whole new multistage refractive index sensor is proposed, which is based on the horizontal displacement of the photonic spin Hall effect. It is found that the angle of displacement is very sensitive to the diversification in the refractive index of the measured analyte, and the angle of horizontal displacement can vary by 12.5 degrees when the refractive index changes by 1. In addition, to further expand the function of this sensor, the multistage refractive index measurement by adjusting the Fermi level of the graphene is realized. Specifically speaking, when the Fermi level is 0.2 eV, the refractive index measurement range of this sensor is 2.2-3.2, and the sensitivity can be up to 7.5 degrees/RIU at this time. Eventually, the transformation of temperature and thicknesses of both the graphene layer and the layer to be measured in the two cases are respectively discussed, and the result is that this sensor has good temperature resistance and the stability of thickness errors in the engineering process. It can be said that the emergence of this new type of sensor will likely have broad application prospects in the measurement field, especially for some special cases of single frequency point work. [ABSTRACT FROM AUTHOR]