Modes, Bounds, and Synthesis of Optimal Electromagnetic Scatterers

TL;DR

This paper develops a method for optimally designing electromagnetic scatterers by synthesizing material distributions based on physical bounds and mode analysis, applicable to arbitrary shapes with explicit solutions for spheres.

Contribution

It introduces a novel synthesis approach combining radiation and characteristic modes for optimal electromagnetic scatterer design, valid for arbitrary shapes.

Findings

Explicit analytical expressions for spherical shapes.

Optimal material distributions maximize extinction, scattering, or absorption.

Method applicable to arbitrary obstacle geometries.

Abstract

This paper presents an optimal synthesis of material distributions in obstacles for maximal extinction, scattering, or absorption. The material synthesis is based on an explicit construction utilizing the current distribution derived from physical bounds excited from the far-field. The bounds are expressed in radiation modes for materials restricted by their resistivity and characteristic modes for materials restricted by the contrast. The results are valid for arbitrary shapes, and analytical expressions are provided for spherical shapes.