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arXiv · 1807.08522

Acoustic Pressure Monopole, Velocity Monopole, and Hybrid Monopole

Suet To Tang·Xiaonan Zhang·Chong Meng·Z. Yang
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Abstract

We show that there are two types of acoustic monopoles, namely the pressure monopoles (PMs) and the velocity monopoles (VMs). Under one wave incidence, only the pressure field near a PM at resonance possesses monopolar symmetry, while for a VM at resonance only the velocity field possesses monopolar symmetry. It is the dipolar response function of the monopoles that dictates whether they are PMs or VMs. A hybrid monopolar device with neither velocity nor pressure field symmetry is also demonstrated by combining a VM and a PM, which exhibits two monopole resonances with neither PM nor VM symmetry. The breaking of symmetry could lead to higher absorption of the subwavelength scale devices.

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Suet To Tang, Xiaonan Zhang, Chong Meng, Z. Yang. 2018-07-23. Acoustic Pressure Monopole, Velocity Monopole, and Hybrid Monopole. https://doi.org/10.1103/physrevapplied.11.014008

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