Coupling Efficiency of Terahertz Antiresonant Reflecting Hollow Waveguides

Chih-Hsien Lai ； Yueh-Chi Lai

《Journal of Innovative Technology》 2卷2期 (2020/09) Pp. 43-46

https://doi.org/10.29424/JIT.202009_2(2).0007

摘要

We numerically investigate the coupling efficiency, i.e., the percentage of coupled power, from the light source to the terahertz antiresonant reflecting hollow waveguides. Numerical results show that the coupling efficiency depends strongly on the operating frequency. To be specific, the coupling efficiency can be well above 90% at most frequencies. However, it drops significantly at the resonant frequencies on account of the mode mismatch between the field distribution of input source and the modal pattern of the waveguide mode. The case where a pipe waveguide is connected to another pipe waveguide of different size is also examined, which is considered important for system integration. It is found that, coupling efficiency between the connected pipe waveguides can be high, but the resonant frequencies should be still avoided for efficient operation.

關鍵字

Coupling efficiency ； antiresonant reflecting waveguides ； hollow waveguides ； terahertz waveguides

參考文獻

Arrand, H. F., Benson, T. M., Loni, A., Krueger, M. G., Thoenissen, M., and Lueth, H. (1997). “Self-aligned porous silicon optical waveguides.” Electron. Lett., 33, 1724-1725.

Chou Chau, C.-T., Chou Chao Y.-F., Huang, H.J., Kumara, N.T.R.N., Kooh, M.R.R., Lim, C.M., and Chiang, H.-P. (2020). “Highly sensitive and tunable plasmonic sensor based on a nanoring resonator with silver nanorods.” Nanomaterials, 10, 1399.

Chou Chau, Y.-F., Chen, K.-H., Chiang, H.-P., Lim, C.M., Huang, H.J., Lai, C.-H., and Kumara, N.T.R.N. (2019a). “Fabrication and characterization of a metallic–dielectric nanorod array by nanosphere lithography for plasmonic sensing application.” Nanomaterials, 9, 1691.

Chou Chau, Y.-F., Chou Chao, C.-T., Huang, H.J., Kumara, N.T.R.N., Lim, C.M., and Chiang, H.-P. (2019b). “Ultra-high refractive index sensing structure based on a metal-insulator-metal waveguide-coupled T-shape cavity with metal nanorod defects.”Nanomaterials, 9, 1433.

Duguay, M.A., Kukubun, Y., Koch, T.L., and Pfeiffer, L. (1986). “Antiresonant reflecting optical waveguides in SiO2-Si multiplayer structures.” Appl. Phys. Lett., 49, 13-15.