Lai Chih-Hsien, You Borwen, Lu Ja-Yu, Liu Tze-An, Peng Jin-Long, Sun Chi-Kuang, Chang Hung-Chun
Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei, 10617, Taiwan.
Opt Express. 2010 Jan 4;18(1):309-22. doi: 10.1364/OE.18.000309.
Modal characteristics of the THz pipe waveguide, which is a thin pipe consisting of a large air core and a thin dielectric layer with uniform but low index, are investigated. Modal indices and attenuation constants are calculated for various core diameters, cladding thicknesses, and cladding refractive indices. Numerical results reveal that the guiding mechanism of the leaky core modes, which transmit most of the power in the air-core region, is that of the antiresonant reflecting guiding. Moreover, modal patterns including modal intensity distributions and electric field vector distributions are shown for the fundamental and higher order modes. Experiments using time-domain spectroscopy with PMMA pipes also confirm the antiresonant reflecting guiding mechanism.
对太赫兹管道波导的模态特性进行了研究，该波导是一种由大空气芯和薄介电层组成的细管，介电层均匀但折射率较低。计算了不同芯径、包层厚度和包层折射率下的模态折射率和衰减常数。数值结果表明，泄漏芯模的导波机制是反谐振反射导波，大部分功率在空气芯区域传输。此外，还给出了基模和高阶模的模态图案，包括模态强度分布和电场矢量分布。使用聚甲基丙烯酸甲酯（PMMA）管进行的时域光谱实验也证实了反谐振反射导波机制。
