Research On Propagation Properties Of Surface Plasmon Waves With Transformation Optics

Surface plasmons (SPs) are a special kind of electromagnetic field, which isstrongly confined to the interface of metal and dielectric medium. Recently with theadvancement of micro-nano machining technology, SPs have been widely used forthe nono-photonics, micro-nano optical devices, integrated optical circuit andmedical biomedical sensing. Due to the serious energy scattering when propagatingon the uneven metal surface, the efficient energy propagation is much based on theflatness of the metal surface, which attracts more and more people’s interests andattentions. Transformational Optics (TO), as a mathematical tool, has been proposedto control the propagation of the electromagnetic waves arbitrarily by designingcomplex electromagnetic medium with unusual properties. With the TO method, westudied the propagation properties of SP waves on the uneven metal surface,designed the turning propagations of SP waves with different angles, and proposedQuasi-Coordinate Transformation (Q-CT). The major achievements in this thesis aresummarized as follows:The turning propagations of SP waves on metal surface with different anglesare designed. By purposely stretching the SP waves surfaces with the TO, acuteturning and quarter turning of the propagation of SP waves are designed, as well asthe horizontal bending of the propagation of SP waves.The Q-CT method is proposed, and applied to the study about the propagationproperties of SP waves on the uneven metal surface. Due to the strong confinementof the intensity, high efficiency of the transmission of the intensity is achieved withQ-CT. After the comparison with the coordinate transformation, three advantages ofQ-CT are found: non-magnetic transformed medium, simple solving process andmore general applications.