| Graphene an ideal two-dimensional material, with the unique mechanical, electronic and optical properties, is being researched in different fields. In this dissertation, we firstly introduce some graphene photonic and optoelectronic devices, and highlight the structure differences used in these devices, then we introduce the total internal reflection (TIR) structure used in our dissertation. Our group has found the polarization-dependent absorption effect and broadband enhanced absorption under TIR, based on which I have made some researches in two directions as follows:Using the Transfer-Matrix method for multilayer structure, we calculate the spectrum-dependent reflection, transmission and absorption of graphene and gold film, in which the tunability of graphene is emphasized. Also we experimentally and theoretically analyzed the different polarization-dependent response of graphene and gold fim under TIR:the gold film has the phenomenon of surface plasma resonant (SPR), in contrast graphene exhibits different polarization-dependent effect. This is because in visible spectrum the response of graphene and gold is different, which can be explained by using different optical constant.Based on the polarization-dependent absorption effect, we then proposed a method to accurately count the number of graphene layers, which is applicable for both exfoliated and chemical vapor deposition (CVD) graphene. With special scanning, the three-dimensional imaging of graphene sample can be achieved to test its uniformity. Compared to other methods, ours is suitable for large area graphene film analysis on transparent substrate, and not affected by graphene interlayer spacing. Moreover, our method can be developed and used in testing other two-dimensional materials (e.g. graphene oxide(GO), MoS2).Finally, we predict that the graphene-TIR structure has many potential applications in various fileds, such as broadband photodectors, optical modulation devices, plasmonic research and so on. |
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