Spoof surface plasmon modes on doubly corrugated metal surfaces at terahertz frequencies
Spoof surface plasmon modes on doubly corrugated metal surfaces at terahertz frequencies
复制标题
太赫兹频率下双波纹金属表面的欺骗表面等离子体模式
DOI：
10.1088/0022-3727/49/23/235501
复制
发表时间：
2016-06-15
影响因子：
3.4
通讯作者：
Liu, Pu-Kun
中科院分区：
文献类型：
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作者：
Liu, Yong-Qiang;Kong, Ling-Bao;Liu, Pu-Kun
假表面等离子体(SSPs)在微波和太赫兹(THz)波段具有许多潜在的应用，如成像和传感、通信、创新的漏波天线和许多其他无源器件。SSP的特殊性质(如极强的近场、增强的注波相互作用)使其在开发新型太赫兹电子源方面特别有吸引力。本文从理论和数值两方面对双波纹金属表面的SSP模进行了研究和分析。用简化的模场展开法得到了对称模和反对称模的SSP色散解析表达式，并用有限积分法进行了验证。此外，还考虑了具有有限恒定电导率的真实铜表面在太赫兹区域的传播损耗。结果表明，随着波纹金属表面间隙的减小，布里渊边界对称模式的渐近频率减小，而反对称模式的渐近频率增加。反对称模比对称模有更大的传播损耗。此外，对称模和反对称模的损耗都随着间隙尺寸的增大而减小。随着沟槽深度的减小，对称模和反对称模的渐近频率都增加，但传播损耗的变化更为复杂。传播损耗随周期的增加而增大。我们对这种具有不同参数的双波纹金属结构上SSP模色散特性和传输损耗的研究对THz波段的光波导、高集成度电路系统、滤波器和大功率电子源等应用具有重要的指导意义。
Spoof surface plasmons (SSPs) have many potential applications such as imaging and sensing, communications, innovative leaky wave antenna and many other passive devices in the microwave and terahertz (THz) spectrum. The extraordinary properties of SSPs (e.g. extremely strong near field, enhanced beam–wave interaction) make them especially attractive for developing novel THz electronic sources. SSP modes on doubly corrugated metal surfaces are investigated and analyzed both theoretically and numerically in this paper. The analytical SSP dispersion expressions of symmetric and anti-symmetric modes are obtained with a simplified modal field expansion method; the results are also verified by the finite integration method. Additionally, the propagation losses are also considered for real copper surfaces with a limited constant conductivity in a THz regime. It is shown that the asymptotical frequency of the symmetric mode at the Brillouin boundary decreases along with the decreased gap size between these two corrugated metal surfaces while the asymptotical frequency increases for the anti-symmetric mode. The anti-symmetric mode demonstrates larger propagation losses than the symmetric mode. Further, the losses for both symmetric and anti-symmetric modes decrease when this gap size enlarges. By decreasing groove depth, the asymptotical frequency increases for both the symmetric and the anti-symmetric mode, but the variation of propagation losses is more complicated. Propagation losses increase along with the increased period. Our studies on the dispersion characteristics and propagation losses of SSP modes on this doubly corrugated metallic structure with various parameters is instructive for numerous applications such as waveguides, circuitry systems with high integration, filters and powerful electronic sources in the THz regime.