Modelling of surface waves on a THz antenna detected by a near-field probe.
Modelling of surface waves on a THz antenna detected by a near-field probe.
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DOI：
10.1364/oe.20.016023
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发表时间：
2012-07
期刊：
影响因子：
3.8
通讯作者：
M. Natrella;O. Mitrofanov;R. Mueckstein;C. Graham;C. Renaud;A. Seeds
中科院分区：
文献类型：
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作者：
M. Natrella;O. Mitrofanov;R. Mueckstein;C. Graham;C. Renaud;A. Seeds
我们基于之前在蝴蝶结天线上进行太赫兹（THz）表面等离子体波成像的工作中使用的亚波长孔径探针对实验系统进行了建模。我们第一次证明了对探头映射的图像所提出的解释的准确性。数值结果与实验结果非常吻合，证明探头探测到的物理量是电场法向分量的空间导数。对近场探头响应的了解现在可以正确解释图像和提取电场的分布。我们还对探针侵入性进行了首次评估，发现天线上的表面等离子体波的图案不会因探针的接近而发生显着改变。这使得该实验系统成为太赫兹天线和其他金属结构近场成像的有效工具。
We have modelled the experimental system based on the sub-wavelength aperture probe employed in our previous work for terahertz (THz) surface plasmon wave imaging on a bowtie antenna. For the first time we demonstrate the accuracy of the proposed interpretation of the images mapped by the probe. The very good agreement between numerical and experimental results proves that the physical quantity detected by the probe is the spatial derivative of the electric field normal component. The achieved understanding of the near-field probe response allows now a correct interpretation of the images and the distribution of the electric field to be extracted. We have also carried out the first assessment of the probe invasiveness and found that the pattern of the surface plasmon wave on the antenna is not modified significantly by the proximity of the probe. This makes the experimental system an effective tool for near-field imaging of THz antennas and other metallic structures.