非对称DBR-金属-DBR结构的光学Tamm态理论研究

Optical Tamm state theory study on asymmetric DBR-metal-DBR structure

作为一种特殊的金属表面态,光学Tamm态(OTS)对光的控制和操作具有独到优势,在新一代光子器件设计中备受青睐.本文基于分布式Bragg反射镜(DBR)-金属-DBR(DMD)结构,通过金属两侧DBR中心频率的失配引入不对称机制,设计和控制可见光区域OTS的产生;通过分析反射谱及电场分布特性,揭示了金属两侧OTS的相互作用及变化规律.结果表明:DMD结构可支持两个不同本征波长OTS存在,失配量δ将影响两个OTS的强度及本征波长,即随着δ变化OTS出现上下两个分支;同时,入射光的偏振态、入射角等也对OTS的强度及本征波长具有明显影响.

As a special metal surface state, optical Tamm state （OTS） has been widely used in designing the new generation of optical devices for its unique advantages in light control and operation. Based on distribute Bragg reflector （DBR）-metal-DBR （DMD）structure, asymmetric mechanism is introduced by mismatching central frequencies of the two DBRs to design and control the generation of OTS. Through the analysis of reflection spectrum and the electric field distribution characteristics, the interaction and variation rules of OTS on each side of metal are revealed. The results indicate that the DMD structure can support the presence of two OTSs with different intrinsic wavelengths. Besides, the mismatch δ will affect the strengths and intrinsic wavelengths of the two OTSs, i.e., the upper and lower branches of OTS appear with the variation of S. In addition, polarization state and injection angle of incident light have a considerable influence on the strength and intrinsic wavelength of OTS.