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Removing singular refractive indices with sculpted surfaces.

ABSTRACT: The advent of Transformation Optics established the link between geometry and material properties, and has resulted in a degree of control over electromagnetic fields that was previously impossible. For waves confined to a surface it is known that there is a simpler, but related, geometrical equivalence between the surface shape and the refractive index, and here we demonstrate that conventional devices possessing a singularity - that is, the requirement of an infinite refractive index - can be realised for waves confined to an appropriately sculpted surface. In particular, we redesign three singular omnidirectional devices: the Eaton lens, the generalized Maxwell Fish-Eye, and the invisible sphere. Our designs perfectly reproduce the behaviour of these singular devices, and can be achieved with simple isotropic media of low refractive index contrast.

SUBMITTER: Horsley SA

PROVIDER: S-EPMC4007085 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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Removing singular refractive indices with sculpted surfaces.

Horsley S A R SA Hooper I R IR Mitchell-Thomas R C RC Quevedo-Teruel O O

Scientific reports 20140502

The advent of Transformation Optics established the link between geometry and material properties, and has resulted in a degree of control over electromagnetic fields that was previously impossible. For waves confined to a surface it is known that there is a simpler, but related, geometrical equivalence between the surface shape and the refractive index, and here we demonstrate that conventional devices possessing a singularity - that is, the requirement of an infinite refractive index - can be ...[more]

PMID: 24786649

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