Existence and uniqueness of Generalized Polarization Tensors vanishing structures

TL;DR

This paper addresses the open problem of the existence and uniqueness of structures with vanishing Generalized Polarization Tensors (GPTs), providing theoretical proofs and numerical validation for specific configurations.

Contribution

It proves existence and local uniqueness of GPT-vanishing structures in 2D and 3D, and establishes global uniqueness for proportional radius configurations.

Findings

Existence of GPT-vanishing structures for given radius configurations.

Global uniqueness in the case of proportional radii.

Numerical examples validating theoretical results.

Abstract

This paper is concerned with the open problem proposed in Ammari et. al. Commun. Math.Phys, 2013. We first investigate the existence and uniqueness of Generalized Polarization Tensors (GPTs) vanishing structures locally in both two and three dimension by fixed point theorem. Employing the Brouwer Degree Theory and the local uniqueness, we prove that for any radius configuration of $N+1$ layers concentric disks (balls) and a fixed core conductivity, there exists at least one piecewise homogeneous conductivity distribution which achieves the $N$-GPTs vanishing. Furthermore, we establish a global uniqueness result for the case of proportional radius settings, and derive an interesting asymptotic configuration for structure with thin coatings. Finally, we present some numerical examples to validate our theoretical conclusions.