静态机械元材料中的非赫米特拓学
Aoxi Wang1, Zhiqiang Meng1, Chang Qing Chen1
1Department of Engineering Mechanics, CNMM and AML, Tsinghua University, Beijing 100084, PR China.
Science advances
|July 5, 2023
概括
研究人员展示了一种在机械超材料中创造非赫密特皮肤效应 (NHSE) 的新方法. 这种被动方法避免了能量增益/损失,为研究非赫米斯物理学提供了一个更简单的平台.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 超材料是指一种超材料.
背景情况:
- 非赫密特皮肤效应 (NHSE) 源于破碎的赫密特性和带拓.
- NHSE通常需要主动控制,并涉及能量增益/损失,限制其实际应用.
- 在机械系统中探索NHSE提供了超越传统波动力学的新途径.
研究的目的:
- 在一个被动机械超材料系统中展示非赫米斯拓.
- 在没有积极控制或能量收益/损失的情况下引入非互惠.
- 为研究非赫尔密斯和非相互现象提供一个可访问的平台.
主要方法:
- 在机械超材料中利用静态变形.
- 通过对网格配置的被动调制引入非互惠性.
- 分析由此产生的拓和皮肤效应现象.
主要成果:
- 在被动机械系统中成功演示了非赫密斯拓.
- 在没有主动控制或能量消耗/放大的情况下实现非互惠.
- 观察到的现象包括相互和更高阶的皮肤效应.
结论:
- 被动机械超材料为实现非赫米特现象提供了一个可行的和简化的平台.
- 这种方法绕过了主动控制和能量增益/损失的需要,扩大了NHSE研究的范围.
- 这项研究为探索机械系统中复杂的非赫米特和非互惠物理学的新可能性打开了大门.
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