Graphene polarization effect based method and device for determining refractive index in real time

The invention provides a graphene polarization effect based method and device for determining refractive index in real time, belonging to the refractive index related fields such as materials, biology and chemistry. Based on the graphene polarization and absorption effects, convex lenses are used for focusing incident light on a prism and substrate material to which graphene is stuck, a polarized beam splitter is used for splitting s polarized beams and p polarized beams, a balanced detector is used for measuring the difference between s polarization electric signals and p polarization electric signals and then the refractive index of the substrate material on which the converging light is focused is obtained. When the refractive index of the substrate changes, the difference between s polarization electric signals and p polarization electric signals also changes, thus the complex refractive index of the susbtrate material can be monitored in real time without any device. The method and the device are suitable for studying real-time conditions of changes of the complex refractive index and the liquid refractive index and large change range and fast change process of the refractive index.