Experiments on Maxwell's fish-eye dynamics in elastic plates
Experiments on Maxwell's fish-eye dynamics in elastic plates
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DOI：
10.1063/1.4905730
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发表时间：
2015-01-12
影响因子：
4
通讯作者：
Sebbah, Patrick
中科院分区：
文献类型：
--
作者：
Lefebvre, Gautier;Dubois, Marc;Sebbah, Patrick
实验证明，厚度分布沿径向分段变化的Duraluminum薄板，h（r）= h（0）（1+（r/R-max）（2））（2），其中h（0）= 0.5 mm，h（R-max）= 2 mm，R-max = 10 cm，在许多方面表现为光学中的麦克斯韦鱼眼透镜。它对中心频率为30 kHz和60 kHz的高斯脉冲的成像特性非常类似于由虚拟球体上的射线轨迹（大圆）预测的那些特性（从北极发出的射线在南极相遇）。然而，作为薄板中弯曲波的色散性质的直接结果，重新聚焦时间取决于载波频率。重要的是，实验结果与时域有限差分模拟吻合良好。(C)2015 AIP Publishing LLC.
We experimentally demonstrate that a Duraluminium thin plate with a thickness profile varying radially in a piecewise constant fashion as h(r) = h(0) (1 + (r/R-max)(2))(2), with h(0) = 0.5 mm, h(R-max) = 2 mm, and R-max = 10 cm, behaves in many ways as Maxwell's fish-eye lens in optics. Its imaging properties for a Gaussian pulse with central frequencies 30 kHz and 60 kHz are very similar to those predicted by ray trajectories (great circles) on a virtual sphere (rays emanating from the North pole meet at the South pole). However, the refocusing time depends on the carrier frequency as a direct consequence of the dispersive nature of flexural waves in thin plates. Importantly, experimental results are in good agreement with finite-difference-time-domain simulations. (C) 2015 AIP Publishing LLC.