Inverse Design of Invisibility Cloaks using the Optical Theorem

TL;DR

This paper introduces an efficient optimization method for designing invisibility cloaks by minimizing forward scattering using the optical theorem, enabling simpler and faster design of structures that reduce scattering.

Contribution

It presents a novel optimization approach based on the optical theorem for designing invisibility cloaks, improving computational efficiency over traditional methods.

Findings

Successfully designed gradient-permittivity cloaks that reduce scattering.

Method applicable to targets of various sizes and shapes.

Demonstrated improved efficiency in cloak design process.

Abstract

We develop and apply an optimization method to design invisibility cloaks. Our method is based on minimizing the forward scattering amplitude of the cloaked object, which by the optical theorem, is equivalent to the total cross section. The use of the optical theorem circumvents the need to evaluate and integrate the scattering amplitude over angle at each iteration, and thus provides a simpler, more computationally efficient objective function for optimizing structures. We implement the approach using gradient descent optimization and present several gradient-permittivity cloaks that reduce scatter by metallic targets of different size and shape.