Performing Mathematical Operations using High-Index Acoustic Metamaterials

TL;DR

This paper introduces a compact acoustic computing system using high-index acoustic metamaterials that directly perform mathematical operations in the spatial domain, eliminating the need for Fourier transform components.

Contribution

It presents a novel, highly compact acoustic computing system based on a simple high-index slab waveguide that operates directly in the spatial domain.

Findings

Demonstrates a compact acoustic computing device without Fourier lenses

Shows potential for high-speed image processing and real-time signal analysis

Achieves direct mathematical operations in acoustic wave systems

Abstract

The recent breakthrough in metamaterial-based optical computing devices [Science 343, 160 (2014)] has inspired a quest for similar systems in acoustics, performing mathematical operations on sound waves. So far, acoustic analog computing has been demonstrated using thin planar metamaterials, carrying out the operator of choice in Fourier domain. These so-called filtering metasurfaces, however, are always accompanied with additional Fourier transform sub-blocks, enlarging the computing system and preventing its applicability in miniaturized architectures. Here, employing a simple high-index acoustic slab waveguide, we demonstrate a highly compact and potentially integrable acoustic computing system. The system directly performs mathematical operation in spatial domain and is therefore free of any Fourier bulk lens. Such compact computing system is highly promising for various applications including high throughput image processing, ultrafast equation solving, and real time signal processing.