Manipulation Surface Plasmon Polariton Based On Topological Insulator

Topological insulators (TIs), quantum electronic materials, have an insulating gap in the bulk that is of spin-orbit origin, and exotic metallic states at their surfaces that are protected by time-reversal symmetry. The emergence of TIs has attracted considerable attention due to their potential applications in quantum computing, spintronic devices and terahertz detectors.Recently, the surface plasmons in a topological insulator (Bi2Se3) have been experimentally observed. This breakthrough is expected to make TI be a promising candidate to the next generation of optoelectronic integrated devices. Meanwhile, the research of the surface plasmon on TIs arouses great enthusiasm and interest, especially in the field of the surface plasmon manipulation. However, the research of TIs has just begun, and a lot of work on manipulation of the surface plasmons is needed.In this paper, firstly, we study the optical properties of the top TI surface, including optical conductivity and permittivity. Besides, we theoretically analyze the characteristics of the surface plasmon polaritons (SPP) supporting on the top TI surface. At last, manipulation of the surface plasmon on the TI is deeply investigated. Our work may lay the foundation for further investigations on TI in future. The main work of this paper includes the following aspects:(1) Introduction of the characteristics, development and international works of TI, especially the research status of TIs in the field of the surface plasmons.(2) Investigation of the characteristics of surface plasmon on TIs. We study the optical properties of the top TI surface, including optical conductivity and permittivity of the time-reversal symmetry-breaking TI surface. On the basis of above analysis, we also theoretically analyze the characteristics of the surface plasmon polaritons (SPP) supporting on a gapped TI-vacuum interface.(3) Investigation of the manipulation of the plasmon resonance on TIs. First, we introduce the numerical method of modeling of topological insulator according to the analysis of the experiment data. The accuracy of the method of modeling of topological insulator is approved by comparing the simulation results with the measured results of plasmon resonance on patterned Bi2Se3 grating. Finally, we further analyze the manipulation of plasmon resonance using thin Bi2Se3 micro-disk arrays.