Thestudy Of Spectral Properties Of Carbon-nano Films Coated Optical Fiber

With the development of optical fiber communication technology, optical fiber sensing technology, computer technology and materials science and technology,the urgent need of the combination of new materials especially nano materials with the existing technology to construct new optical devices to meet the future needs of data transmission and signal processing, is attracting more and more researchers in big data era.As two kinds of nano allotrope of carbon atoms, graphene is two-dimensional plane like honey-comb lined by a single layer of carbon atoms, and carbon nanotubes(CNT) is one-dimensional tubular structure rolled by a single layer of carbon atoms.Combining them with optical fiber, utilizing optical fiber sensor coated with carbon nano film in refractive index, gas, humidity, volatile organic compounds and biological parameters .detection areas,researching on its theoretical and experimental spectral characteristics is the basic work of developing devices.In this paper, setting carbon nano-film Mach-Zehnder interferometer and Michelson interferometer as the research object, four film coated optical fiber structures were proposed,their spectral characteristics and sensing properties were also discussed. The main research contents in this paper include:In chapter 1,the research status of carbon nanotubes and graphene in the optical fiber sensing field was briefly discussed. A variety of coating methods were also summarized.In chapter 2,working principle and theoretical model of Mach-Zehnder interferometric optical fiber sensor and Michelson interferometric optical fiber sensor were expounded in detail. What's more, the characteristics of carbon nanotubes and graphene were discussed amply to demonstrate the theoretical feasibility of utilizing carbon materials in optical fiber sensing area especially in the interferometric optical fiber sensor fabrication area.In chapter 3,experimental research about carbon nanotube coated Mach-Zehnder interferometric optical fiber sensor was discussed and the influence of carbon nanotube film to the optical spectrum was also explored .The fabrication process of the film coated sensor was introduced in detail and its performance in temperature and refractive index sensing areas was shown.In chapter 4,experimental research about graphene coated Mach- Zehnder interferometric optical fiber sensor is discussed and the influence of graphene film to the optical spectrum is also explored. Sensor was made and its performance in temperature and refractive index sensing areas were experimented. The results were also compared with Mach-Zehnder interferometric optical fiber sensor.In chapter 5, this two different kinds of carbon nano films were coated on Michelson interferometric optical fiber sensor separately and their influence on optical fiber sensing performance in temperature and refractive index sensing areas were also experimented.