机械元材料的静态非互惠性
Corentin Coulais1,2, Dimitrios Sounas3, Andrea Alù3
1AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands.
Nature
|February 14, 2017
概括
研究人员在静态机械超材料中展示了破碎的互惠性. 这些材料表现出不对称的反应和单向放大,
科学领域:
- * 物理
- * 材料科学
- * 超材料
背景情况:
- 互惠是物理学的基本原则,确保两个点之间的对称信号传输.
- * 破解互惠 (非互惠) 允许对信号传输和隔离进行加强控制.
- *以前的非互换装置主要在动态系统 (电磁,声学,机械波) 中运行.
研究的目的:
- * 为了证明静态机械系统中的互惠性.
- 实现具有不对称响应和单向放大的机械超材料.
- * 探索静态非互惠的应用.
主要方法:
- * 开发具有较大的非线性性的机械超材料.
- * 将几何不对称和/或拓特征整合到元材料设计中.
- * 实验测试静态机械对不同侧面的激发反应.
主要成果:
- 根据激发方向显示显著不同的输出位移的机械超材料.
- 在静态条件下证明了单向位移放大.
- * 将非互惠原则从动态系统扩展到静态系统.
结论:
- 在静态机械系统中可以打破互惠,挑战以前的限制.
- 不相互的元材料为信号控制,隔离和能量操纵提供了新的可能性.
- 潜在的应用包括能量吸收,转换,收获,软机器人,假肢和光学机械.
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