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arXiv · 2103.11581

Sound Trapping in an Open Resonator

Lujun Huang·Yan Kei Chiang·Sibo Huang·Chen Shen·Fu Deng·Yi Cheng·Bin Jia·Yong Li·David A Powell·Andrey E Miroshnichenko
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Abstract

The ability of extreme sound energy confinement with high-quality factor (Q-factor) resonance is of vital importance for acoustic devices requiring high intensity and hypersensitivity in biological ultrasonics, enhanced collimated sound emission (i.e. sound laser) and high-resolution sensing. However, structures reported so far demonstrated a limited quality factor (Q-factor) of acoustic resonances, up to several tens in an open resonator. The emergence of bound states in the continuum (BIC) makes it possible to realize high-Q factor acoustic modes. Here, we report the theoretical design and experimental demonstration of acoustic BICs supported by a single open resonator. We predicted that such an open acoustic resonator could simultaneously support three types of BICs, including symmetry protected BIC, Friedrich-Wintgen BIC induced by mode interference, as well as a new kind of BIC: mirror-symmetry induced BIC. We also experimentally demonstrated the existence of all three types of BIC with Q-factor up to one order of magnitude greater than the highest Q-factor reported in an open resonator.

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Lujun Huang, Yan Kei Chiang, Sibo Huang, Chen Shen, Fu Deng, Yi Cheng, Bin Jia, Yong Li, David A Powell, Andrey E Miroshnichenko. 2021-03-22. Sound Trapping in an Open Resonator. https://doi.org/10.1038/s41467-021-25130-4

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