Gradient Index Devices for the Simultaneous Focusing of the S0 and A0 Lamb Modes

Yabin Jin; Daniel Torrent; Yan Pennec; Yongdong Pan; Bahram Djafari-Rouhani

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arXiv · 1502.05423

Gradient Index Devices for the Simultaneous Focusing of the S0 and A0 Lamb Modes

Yabin Jin·Daniel Torrent·Yan Pennec·Yongdong Pan·Bahram Djafari-Rouhani

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Abstract

Gradient index devices for the simultaneous control of the S 0 and A 0 Lamb modes are presented and numerically analysed. It is found a special relationship between the refractive indexes for these two modes which allows their simultaneous control by means of graded phononic crystals and thickness variations of the plate. A flat gradient index lens and a circular Luneburg lens are designed. Numerical simulations show that the performance of these devices is good for the two modes in a broadband frequency region, and that this approach can be used to design more advanced refractive devices for the total control of guided vibrational modes.

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Yabin Jin, Daniel Torrent, Yan Pennec, Yongdong Pan, Bahram Djafari-Rouhani. 2015-02-18. Gradient Index Devices for the Simultaneous Focusing of the S0 and A0 Lamb Modes. https://arxiv.org/abs/1502.05423

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