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Abstract Acoustic non-reciprocity, referring to the phenomenon of path-dependent propagation, has diverse applications in mechanical devices. This paper presents a numerical study on a periodic triangle-shape structure that breaks reciprocity in a passive manner over a broad range of frequency and energy. The proposed structure contains strong nonlinearity and geometric asymmetry, which contributes to a direction-dependent dispersion relationship. When the signal frequency falls in the band pass in one direction, and band gap in the other, a unidirectional wave propagation results. The system achieves giant non-reciprocity with minimal distortion in the frequency content of the signal.
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Broadband Acoustic Non-reciprocity in a Passive, Nonlin-ear Metamaterial
Acoustic reciprocity, which is widely observed in linear time-invariant systems, refers to the property that wave transmission pattern remains the same when the source and receiver are switched. Non-reciprocity, on the other hand, violates this symmetry and can be used to control wave propagation and manufacture desired propagation patterns. To break reciprocity, multiple approaches (active and passive) have been studied recently. While active manner often relies on odd-symmetry field or time-variant parameters, passive manner achieves non-reciprocity by combining geometric asymmetry and nonlinearity in the structure. In this field, researchers have studied a number of acoustic devices that allow one-way propagation1, 2. However, these devices either change the frequency content of the sending signal, or have a strict restriction on the range of sending frequency. In this paper, we propose a passive, nonlinear, periodic structure, which achieves giant non-reciprocity for a range of input frequency and energy with minimal distortion of the sending frequency.
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- Award ID(s):
- 1741565
- PAR ID:
- 10173333
- Date Published:
- Journal Name:
- PHONONICS 2019: 5th International Conference on Phononic Crystals/Metamaterials, Phonon Transport and Topological Phononics
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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