1次元フォトニック結晶結合ラインの電磁波伝播特性

by 武田 三男
北原さん(福井大学)のDC時代のマイクロストリップラインによる電磁波の制御の研究を最近まとめ直して論文化しました。そのうちの周期構造を導入した2つのストリップラインを上下に重ねた結合ラインの電磁波伝播特性の論文[1]とそのシミュレーションを中田さん(大阪大学)にお願いしてJPSJに発表した論文[2]の内容を紹介します。

[1] H. Kitahara, Y. Suzuki, J. Miyashita, and M. W. Takeda, “Electromagnetic Property of Coupled System of One-Dimensional Photonic Crystal”, J. Phys. Soc. Jpn. 88, 044702 (2019).
[2] H. Kitahara, Y. Nakata, Y. Suzuki, J. Miyashita, F. Miyamaru, and M. W. Takeda, “Spatial Field Distributions of Electromagnetic Waves in Coupled System of One-Dimensional Photonic Crystals”, J. Phys. Soc. Jpn. 90, 044708 (2021).

[2]のアブストラクト
Recently, we proposed and validated a novel electromagnetically coupled waveguide system of strip lines configured with a pair of closely aligned one-dimensional photonic crystals as a microwave component with multiport. The transmission and reflection spectra are calculated by the method of moment and observed by a vector network analyzer. The both special transmission characteristics of the coupled line and of the photonic crystal are observed. Inside the photonic band gap region, the transmission spectra become opaque because of the absence of electromagnetic modes that are unique to the photonic crystal. Outside the photonic band gap region, the transmission characteristics from the incident port on a transmission line to the exit port on the other line show reflection characteristics. This is because only the odd-modes are coupled between two closely aligned transmission lines.[1] In this study we will show the numerical analysis results of the spatial distributions of the current of the typical electromagnetic wave modes such as standing wave modes and those at the band gap center and edges by the finite element method in order to confirm the hybrid effect of coupled and periodic line system and will discuss the propagation properties of these modes.