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arXiv · 2410.20377

Acoustic Zero-Index Metamaterials for Leaky-Wave Antennas

keqiang Lyu·Ying Wu
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Abstract

In this work, we introduce an advanced acoustic leaky-wave antenna employing zero-refractive-index metamaterials (ZIMs) that significantly surpasses traditional designs in terms of radiation ef-ficiency and directivity. Our design features a novel space-coiling structure, which manipulates the Dirac-like dispersion based on accidental degeneracy to achieve double-zero-index metamaterials (DZIM). The newly developed acoustic Dirac leaky-wave antenna (ADLWA) achieves more than double the radiation efficiency of conventional antennas based on arrays with side holes and mem-branes. It exhibits superior directional control, allowing for precise beam scanning by adjusting the frequency. Additionally, the ADLWA functions effectively as a passive sonar system, capable of de-tecting the direction of moving sound sources. This breakthrough enhances acoustic wave control and promises significant advancements in sensing and communication technologies.

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keqiang Lyu, Ying Wu. 2024-10-27. Acoustic Zero-Index Metamaterials for Leaky-Wave Antennas. https://arxiv.org/abs/2410.20377

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