【摘要】 基于时域有限差分(FDTD)法,从麦克斯韦方程组出发,结合周期边界条件将完全匹配层SAC-PML吸收边界条件应用到所建立的光栅数值模型中。对光栅结构和光滑表面结构的光谱特性进行了数值计算,得到了TM波入射时结构的吸收率,讨论了金属光栅耦合的表面等离子极化(SPPs)和空腔谐振模(Microcavity Mode)现象。结果表明由于表面等离子效应和空腔谐振现象的存在,与光滑表面相比光栅表面的吸收率得到了显著的增强。更多还原

【Abstract】 Based on the Finite-Difference Time-Domain(FDTD) method,the perfectly matched layer (SAC-PML) absorbing boundary conditions(ABCs) combined with periodic boundary conditions (PBCs) were applied to the grating numerical model.Numerical calculations of spectral properties of the grating and smooth-surface structures were carried out.Absorptance of these two structures was obtained when the TM wave was used as the incident wave,and the metallic grating-coupled surface plasmon polarizations(SPPs) and the microcavity mode were discussed.The results indicate that,the absorptance of grating structure can be enhanced significantly compared with that of smooth-surface structure due to the present of SPPs and microcavity mode.更多还原