# Acoustic cloaking: geometric transform, homogenization and a genetic algorithm

## TL;DR

This paper presents a novel method combining geometric transformation, homogenization theory, and genetic algorithms to design anisotropic metamaterials for acoustic cloaking, enabling practical cloaks with existing manufacturing techniques.

## Contribution

It introduces an integrated approach to design complex cloaking metamaterials using coordinate transformations, homogenization, and optimization algorithms.

## Key findings

- Successfully designed three types of cloaks with isotropic layers
- Cloaks mimic the behavior of ideal transformed materials
- Numerical simulations confirm effective cloaking performance

## Abstract

A general process is proposed to experimentally design anisotropic inhomogeneous metamaterials obtained through a change of coordinate in the Helmholtz equation. The method is applied to the case of a cylindrical transformation that allows to perform cloaking. To approximate such complex metamaterials we apply results of the theory of homogenization and combine them with a genetic algorithm. To illustrate the power of our approach, we design three types of cloaks composed of isotropic concentric layers structured with three types of perforations: curved rectangles, split rings and crosses. These cloaks have parameters compatible with existing technology and they mimic the behavior of the transformed material. Numerical simulations have been performed to qualitatively and quantitatively study the cloaking efficiency of these metamaterials.