Research On Temperature Sensing Of GO/Microstructured Fiber Based On Finite Element

Microstructured optical fiber has a wide range of applications in the fields of biomedicine,environmental monitoring and control,chemical testing,and food safety testing.Nanomaterials graphene and not only play a good role in sensitizing the photosensitive area of optical waveguide devices,but also play a role in protecting the metal layer from oxidation in sensors based on surface plasmon resonance(SPR).Compared with the existing optical fiber temperature sensors,this paper combines the advantages of high sensitivity,strong stability,strong electromagnetic interference resistance and simple structure preparation of the composite waveguide of graphene oxide and microstructured optical fiber.Machzend(MZ)sensor unit preparation and device sensitivity analysis,finite element simulation theory research and structural design have been researched,and a temperature sensing system based on finite element graphene oxide composite microstructure fiber has been proposed and designed.The principle that the sensitive materials graphene oxide and microstructured optical fiber caused changes in physical quantities such as refractive index and conductivity under temperature changes was systematically analyzed.Comsol full vector finite element simulation software is used to simulate the electric field of fiber-optic composite sensitive material sensing units with different structures.Theoretical derivation and simulation analysis of the material properties of different sensing units and the influence of the waveguide micro-size on the energy distribution of the electric field laid a theoretical foundation for the research of micro-structured fiber temperature sensing.A graphene oxide preparation platform was constructed,and the graphene oxide floc was obtained by ice-water bath,freeze-drying,and centrifugation.Different MZ sensor heads were made by the optical fiber fusion taper method,and the middle20 mm SMF was tapered to form MCF,which was coated with graphene oxide,and then a straight-through optical path MZ temperature sensor system was built.Atemperature sensing system with a sensitivity of 23.7pm/? in the temperature range from 25? to 75? was realized.A dual-core high birefringence PCF-SPR temperature sensor was designed.The central hole wall was plated with gold film and filled with toluene solution with high temperature sensitivity coefficient to realize sensing.The background substrate refractive index,air hole size,and gold film thickness were selected.Such effects are considered to ensure accuracy.Numerical analysis results show that the birefringence of the sensor structure is as high as 0.0052;the average sensitivity can be achieved in the temperature range of 0? ? 80?,12.695nm/?,and the corresponding resolution is 0.00725?.Compared to uncoated GO and existing sensing units,the birefringence,stability and sensitivity of the sensor are improved.