All-dielectric self-cloaked structures

TL;DR

This paper introduces a novel method for designing self-cloaked dielectric structures that are intrinsically invisible by matching their optical properties to the environment, using simple isotropic materials without external cloaks.

Contribution

It presents an innovative design principle for creating self-cloaked objects that are indistinguishable from their surroundings across a range of frequencies using only dielectric materials.

Findings

Experimental validation at microwave frequencies confirms the design's effectiveness.

The method works for arbitrarily shaped objects within specified bandwidths.

No loss or gain materials are required for achieving invisibility.

Abstract

While practical realizations of optical invisibility have been achieved so far by various ingenious methods, they generally rely on complex materials which prevent the wide implementation of such schemes. Here, we propose an alternative indivisibility procedure to design objects (i.e. self-cloaked structures) that have optical properties identical to the surrounding environment and are, thereby, intrinsically invisible to an external observer as such (without the necessity of an external cloak). The proposed method is based on the uncoupling of the scattered waves from the incident radiation by judiciously manipulating the scattering potential of a given object. We show that such a procedure is able to yield optical invisibility for any arbitrarily shaped object within any specified frequency bandwidth by simply employing isotropic non-magnetic dielectric materials, without the usage of loss or gain material. The validity of the design principle has been verified by direct experimental observations of the spatial electric field profiles and scattering patterns at the microwave regime. Our alternative self-cloaking strategy may have profound implications especially in noninvasive probing and cloaked sensor applications, where the wave penetrability into the sensor region is essential together with its invisibility to minimize the field distortion.