文章基本信息

标题：Subwavelength Acoustic Valley-Hall Topological Insulators Using Soda Cans Honeycomb Lattices
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作者：Zhiwang Zhang ; Ye Gu ; Houyou Long 等
期刊名称：Research
电子版ISSN：2639-5274
出版年度：2019
卷号：2019
页码：1-8
DOI：10.34133/2019/5385763
语种：English
出版社：American Association for the Advancement of Science
摘要：Topological valley-contrasting physics has attracted great attention in exploring the use of the valley degree of freedom as a promising carrier of information. Recently, this concept has been extended to acoustic systems to obtain nonbackscattering sound propagations. However, previous demonstrations are limited by the cut-off frequency of 2D waveguides and lattice-scale size restrictions since the topological edge states originate from Bragg interference. Here we engineer topologically valley-projected edge states in the form of spoof surface acoustic waves that confine along the surface of a subwavelength honeycomb lattice composed of 330-mL soda cans. The inversion symmetry is broken through injecting a certain amount of water into one of the two cans in each unit cell, which gaps the Dirac cone and ultimately leads to the topological valley-Hall phase transition. Dual-frequency ranges of the valley-projected edge states below the sound line are observed, which originate from the first-order and second-order resonances, respectively. These results have the potential to enable promising routes to design integrated acoustic devices based on valley-contrasting physics.