Effects of graphene membrane parameters on diaphragm-type optical fibre pressure sensing characteristics

摘要

Considering the potential application of graphene in optical fibre Fabry-Perot pressure-sensitive membrane, a constitutive model for strain-induced deformation characteristics of graphene membrane was established based on the large deflection elastic theory of circular membrane. The effects of membrane parameters, including pre-stressing force, Young's modulus and membrane layer number on deflection mechanical behaviours were studied by using finite element method. The simulation results demonstrated that the pre-stressing force had a significant impact on the deflection deformation and natural frequency with small loads. And the values of Young's modulus should also be considered with large applied loads, because of the imperfect high-quality and uniform graphene preparation methods. Then we carried out a computational study of the effects of membrane thickness on its reflectivity with Fresnel's equations. It was shown that a single-layered graphene membrane with 25 mu m diameter can achieve an approximate sensitivity of 80 nm/kPa for a 40 mu m Fabry-Perot cavity.