MEMS approach to low-frequency broadband acoustic metamaterials

TL;DR

This paper presents a MEMS-based method for creating broadband acoustic metamaterials that significantly improve sound attenuation at low frequencies, demonstrating practical experimental results.

Contribution

It introduces a novel MEMS metastructure, particularly cavity-backed micromembranes, achieving notable sound transmission loss improvements over traditional methods.

Findings

Nearly 6 dB average increase in sound attenuation from 200 Hz to 1200 Hz.

22.3% gain in sound transmission loss using cavity-backed micromembranes.

Effective broadband attenuation demonstrated in experimental setup.

Abstract

We experimentally demonstrate a simple micro-electro-mechnical systems (MEMS) approach to acoustic metamaterials and have observed the average increase of nearly 6 dB beyond the classic law for sound attenuation at low frequencies from 200 Hz to 1200 Hz. Here, we have also found that the MEMS metastructure, especially the cavity-backed micromembrane, contributes to 22.3% gain of sound transmission loss (STL) with a fill factor of perforation of less than 7.6%.