このエントリーをはてなブックマークに追加
ID 64022
フルテキストURL
fulltext.pdf 8.38 MB
著者
Kataoka, Motoki Department of Electrical and Electronic Engineering, Okayama University
Misawa, Masaaki Department of Electrical and Electronic Engineering, Okayama University ORCID Kaken ID publons researchmap
Tsuruta, Kenji Department of Electrical and Electronic Engineering, Okayama University ORCID Kaken ID publons researchmap
抄録
Based on the concept of band topology in phonon dispersion, we designed a topological phononic crystal in a thin plate for developing an efficient elastic waveguide. Despite that various topological phononic structures have been actively proposed, a quantitative design strategy of the phononic band and its robustness assessment in an elastic regime are still missing, hampering the realization of topological acoustic devices. We adopted a snowflake-like structure for the crystal unit cell and determined the optimal structure that exhibited the topological phase transition of the planar phononic crystal by changing the unit cell structure. The bandgap width could be adjusted by varying the length of the snow-side branch, and a topological phase transition occurred in the unit cell structure with threefold rotational symmetry. Elastic waveguides based on edge modes appearing at interfaces between crystals with different band topologies were designed, and their transmission efficiencies were evaluated numerically and experimentally. The results demonstrate the robustness of the elastic wave propagation in thin plates. Moreover, we experimentally estimated the backscattering length, which measures the robustness of the topologically protected propagating states against structural inhomogeneities. The results quantitatively indicated that degradation of the immunization against the backscattering occurs predominantly at the corners in the waveguides, indicating that the edge mode observed is a relatively weak topological state.
キーワード
phononic crystal
topological acoustic
elastic waveguide
backscattering length
lamb wave
発行日
2022-10-13
出版物タイトル
Symmetry
14巻
10号
出版者
MDPI
開始ページ
2133
ISSN
2073-8994
資料タイプ
学術雑誌論文
言語
英語
OAI-PMH Set
岡山大学
著作権者
© 2022 by the authors.
論文のバージョン
publisher
DOI
Web of Science KeyUT
関連URL
isVersionOf https://doi.org/10.3390/sym14102133
ライセンス
https://creativecommons.org/licenses/by/4.0/