Directional radiation of sound waves by a subwavelength source
Classical Physics
2018-04-04 v2
Abstract
We propose and experimentally achieve a directional dipole field radiated by an omnidirectional monopole source enclosed in a subwavelength structure of acoustically hybrid resonances. The whole structure has its every dimension at an order smaller than the sound wavelength. The significance is that the radiation efficiency is up to 2.3 of the radiation by traditional dipole consisting of two out-of-phase monopoles in the same space. This study eventually takes an essential step towards solving the long-existing barrier of inefficient radiation of directional sound waves in low frequencies, and inspires the ultimate radiation of arbitrary multipoles or even a highly directional beam by a monopole in limited spaces.
Keywords
Cite
@article{arxiv.1702.07277,
title = {Directional radiation of sound waves by a subwavelength source},
author = {Xu-Dong Fan and Yi-Fan Zhu and Bin Liang and Jian-chun Cheng and Likun Zhang},
journal= {arXiv preprint arXiv:1702.07277},
year = {2018}
}