鼓动共振模式和极端功率流量在异型弹性板块中的歪曲
Daniel A Kiefer1, Sylvain Mezil1, Claire Prada1
1Institut Langevin, ESPCI Paris, Université PSL, CNRS, 75005 Paris, France.
Science advances
|December 20, 2023
概括
在异构介质中的弹性波表现出不寻常的功率流动行为. 激光-超声波实验揭示了中独特的现象,包括零组速度模式和共振模式.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 声学 声学 在声学上
背景情况:
- 不同类型材料中的弹性波可以显示与波向量不一致的功率流.
- 这种现象对板块结构中的引导波行为有重大影响.
研究的目的:
- 用激光-超声波来实验地研究单晶晶片中独特的波浪现象.
- 为了识别和描述与功率流直角于它们的波向量波的波.
- 探索零组速度 (ZGV) 模式的存在和行为.
主要方法:
- 使用激光-超声波实验来激发和探测晶片中的弹性波.
- 使用脉冲线源来激发特定的波包.
- 通过实验观测分析波传播和识别零组速度模式.
主要成果:
- 在晶片中观察到具有垂直于它们的波向量功率流的弹性波.
- 确定了一个与脉冲线源平行辐射的波包,与直角功率流相一致.
- 证实了沿着晶体轴的零功率流 (ZGV模式) 的八个特定平面波的存在.
结论:
- 这项研究通过实验证实了与异构介质中缓慢波相关的显著现象.
- 零组速度模式在观察到的波传播和共振模式中起着至关重要的作用.
- 脉冲刺激自然会产生复杂的共振模式,包括移动的节点曲线,由于ZGV模式.
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