在局部共振的元材料中,单一的拓边缘状态
Yeongtae Jang1, Seokwoo Kim1, Eunho Kim2
1Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
Science bulletin
|January 25, 2025
概括
拓边缘状态现在可以在局部共振诱导带隙 (LRGs) 中通过同时过渡拓相和带隙而出现. 这使得超材料中的高度局部化模式成为可能,扩大了拓材料设计的可能性.
科学领域:
- 拓学的元材料 拓学的元材料
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 是一种材料科学.
背景情况:
- 带拓为光子,音声和元材料系统提供了新的材料设计策略.
- 苏 - 施里弗 - 希格尔 (SSH) 模型解释了布拉格型间隙 (BGs) 内的拓内间隙状态.
- 局部共振诱导带隙 (LRGs) 产生于强的合,但在它们内部实现拓边缘状态是具有挑战性的.
研究的目的:
- 为了证明局部共振诱导带隙 (LRGs) 内的拓边缘状态的出现.
- 为了研究LRG拓状态的拓相和带隙过渡的同时实现.
- 在LRG中探索高度局部化模式的潜力.
主要方法:
- 模拟局部共振元材料的反向对称扩展的Su-Schrieffer-Heeger (SSH) 链.
- 使用局部共振颗粒基超材料的实验演示.
- 分析波局部化,以区分BG和LRG的拓模式.
主要成果:
- 拓边缘状态通过同时的拓和带隙过渡在LRG中成功出现.
- 在LRG中,这些拓状态导致高度局部化的模式,类似于波长下单位细胞.
- 实验结果显示,在BG与LRG的拓保护模式中,波局部化模式是不同的.
结论:
- 拓边缘状态可以在局部共振诱导的带隙内实现.
- 这项工作将拓学概念的适用性扩展到更广泛的元材料带隙机制.
- 这些发现为具有增强波局部化特性的新型元材料设计铺平了道路.
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