Ventilation barriers allowing simultaneous sound blocking and free airflow passage are of great challenge but necessary for particular scenarios calling for sound-proofing ventilation. Previous works based on local resonance or Fano-like interference serve a narrow working range around the resonant or destructive-interference frequency. Efforts made on broadband designs show a limited bandwidth typically smaller than half an octave. Here, we theoretically design an ultra-broadband ventilation barrier via hybridizing dissipation and interference. Confirmed by experiments, the synergistic effect from our hybrid-functional metasurface significantly expand the scope of its working frequencies, leading to an effective blocking of more than 90% of incident energy in the range of 650-2000 Hz, while its structural thickness is only 53 mm (∼λ/10). Our design shows great flexibility in customizing the broadband and is capable of handling sound coming from various directions, which has potential in air-permeable yet sound-proofing applications.
@article{arxiv.2010.08160,
title = {Ultra-broadband acoustic ventilation barriers via hybrid-functional metasurfaces},
author = {Ruizhi Dong and Dongxing Mao and Xu Wang and Yong Li},
journal= {arXiv preprint arXiv:2010.08160},
year = {2021}
}