Properties Analysis For Micro-Nano Photonic Components Based On Surface Plasmon Polaritons

With the properties of transmission enhancement and sub-wavelength localization, photoniccomponents based on surface plasmon polaritons meet the requirements of microminiaturizationand integration, which have become one of hot points of nano-photonics recently.Surface plasmon polaritons theories and numerical analysis methods is briefly discussed in thethesis. Based on these theories, the phenomenon of extraordinary optical transmission and focusedlight field on sub-wavelength scale is mainly researched. The main works of the thesis are asfollows:The effect of varied parameters such as metal material, medium refractive, incident lightwavelength, thickness of metal to surface plasmon polaritons excitation in the kretschmannstructure is analyzed. The simulation results show when the thickness of gold film is about60nm,surface plasmon polaritons can be excited easily. When incident light wavelength is over700nm,the angle of incident light requires extremely accuracy.Transmission enhancement of surface plasmon polaritons in sub-wavelength slit and groove isstudied. The study shows that the slit can be considered a Fabry-Perot cavity. When the thickness ofthe film is integer times of the standing wave period, the transmitted intensity can reach maximum.The structure designed can enhance emergent light intensity four times than incident light.A kind of nano-slit photonic component is proposed. The theoretical studies and simulationsshow that various slit width in nano-slit structure is corresponding different effective refractiveindex, so that the phase of light passing through various slit is different. The nano-slit structuredesigned has ideal focusing spot size, traditional photonic devices do not have. Focal length has thesame size as wavelength and half-width is shorter than a wavelength.The thesis embeds liquid crystals in the slit region, which can modulate the focal spot withoutchanging the component geometry. By the control of external electric field, the orientation of liquidcrystals molecules can be changed, thus the refractive index can be altered. Under the conditionwith and without voltage, focal length and full width at half maximum are both different.