亚波长金属光栅的凹槽深度对太赫兹伪表面等离子体影响

从理论上详细研究了一维亚波长金属光栅的凹槽深度对太赫兹伪表面等离子的影响。分别对一维标准亚波长金属光栅和缺陷亚波长金属光栅进行了研究。电场分布情况采用了COMSOL软件进行模拟。得到的结论是:对于一维标准亚波长金属光栅，沿金属光栅传播的表面等离子体取决于槽深度，较深的槽具有更强的束缚能力；对于具有缺陷的光栅结构，电场强度的分布特点取决于缺陷槽的深度，这归功于缺陷槽对光的反射和散射。基于这一理论研究，这两种不同的亚波长金属光栅结构能为太赫兹器件如波导、衰减器及滤波器发展提供新的途征。

Impact of groove depth of subwavelength metal grating on THz spoof SPPs

The influence of groove depth in one dimensional (1D) subwavelength metal grating on THz spoof surface plasmon ploaritons(SPPs) was theoretically investigateal in detail. Two device geometries were proposed including uniform groove depth 1D metal grating and defect groove depth 1D metal grating. The electric field distribution of metal grating was stimulated by employing COMSOL software. For the uniform structure, the dispersion relation of SPPs propagating along grating can be tailored by groove depth. The metal grating with deeper groove has stronger THz electric field distribution and the spoof SPPs is better confined to grating surface. For the defect structure, electric field distribution characteristics of both sides are determined by the defect groove depth, which can be attributed to reflection and scattering of defect. Based on the proposed theoretical stimulation, the two different subwavelength metal grating structures can provide new functionality for THz wave devices such as wave guiding, attenuator and filter.