Enhancement of polarizabilities of cylinders with cylinder-slab resonances

TL;DR

This paper demonstrates that coupling small cylinders with a superlens metamaterial slab can significantly enhance their polarizability through a collective resonance, improving detectability and electromagnetic force effects.

Contribution

It introduces a novel collective resonant mode between cylinders and slabs that enhances polarizability, distinct from individual resonances or cloaking effects.

Findings

Enhanced polarizability via cylinder-slab resonance

Potential for increased electromagnetic forces

Relation to cloaking by anomalous resonance

Abstract

If an object is very small in size compared with the wavelength of light, it does not scatter light efficiently. It is hence difficult to detect a very small object with light. We show using analytic theory as well as full wave numerical calculation that the effective polarizability of a small cylinder can be greatly enhanced by coupling it with a superlens type metamaterial slab. This kind of enhancement is not due to the individual resonance effect of the metamaterial slab, nor due to that of the object, but is caused by a collective resonant mode between the cylinder and the slab. We show that this type of particle-slab resonance which makes a small two-dimensional object much brighter is actually closely related to the reverse effect known in the literature as cloaking by anomalous resonance which can make a small cylinder undetectable. We also show that the enhancement of polarizability can lead to strongly enhanced electromagnetic forces that can be attractive or repulsive, depending on the material properties of the cylinder.