Applications Of Surface Plasmon Polaritons’ Grating And ATR Coupling Model

With the development of nanotechnology and the rise of plasmonics photonics,novel effects and its applications of light presented in metal micro-nano structures havecaused widespread concern, which have become a hot spot of the field. In this paper, amore comprehensive overview of surface plasmon development process is presented.Based on surface plasmon dispersion relationship, the grating coupler, prism couplerand some of their applications are studied.Surface plasmon wave solution and its features on the metal/dielectric interface areanalyzed theoretically, then the dispersion relation of surface plsmon is derived.According to its dispersion relation, surface plasmon coupling modes are introduced,and three characteristic lengthes of surface plasmon are described.The grating coupler applied to optimize the emitted beam of the quantum cascadelasers (QCLs) is studied. Based on the theory of the antenna array, the collimationresults which has been affected by the number of grating grooves, electric field intensityratio between the groove and the slot, the grooves phase and other factors are calculated.Coupling efficiency between the collimated beam and single-mode fiber with the prismis studied. The interpretation and discussion about the fiber type, the location of eachdevice, and the coefficient of coupling efficiency are presented; The finall effectiveoptical power of QCLs is estimated.The influence of the roughness on the dispersion relation, reflectivity andtransmittivity of this structure is discussed. Then, according to the characteristics oflight distribution in unit solid angle and the distribution of dipole function, the spectraldensity function which can determine the roughness parameters is derived and discussed.Based on the phenomenon that while the lower-medium in this structure has beenchanged slightly, the reflectivity will been very different, the sensing characteristics ofthe structure are discussed, and a comprehensive analysis of the effects of eachdielectric layer and temperature on the sensing are performed.