A spherical perfect lens

TL;DR

This paper explores spherical shells of negative refractive index materials as perfect lenses capable of magnifying near-field images, extending the concept from flat slabs to curved geometries with specific spatial dispersion properties.

Contribution

It introduces spherical perfect lens solutions with spatially dispersive negative refractive materials, enabling magnification of sub-wavelength images in near-field regimes.

Findings

Spherical negative refractive shells can act as perfect lenses with magnification.

Conditions for TM and TE modes become independent of permeability and permittivity.

Spatial dispersion with specific radial dependence is essential for lens functionality.

Abstract

It has been recently proved that a slab of negative refractive index material acts as a perfect lens in that it makes accessible the sub-wavelength image information contained in the evanescent modes of a source. Here we elaborate on perfect lens solutions to spherical shells of negative refractive material where magnification of the near-field images becomes possible. The negative refractive materials then need to be spatially dispersive with $\epsilon(r) \sim 1/r$ and $\mu(r)\sim 1/r$. We concentrate on lens-like solutions for the extreme near-field limit. Then the conditions for the TM and TE polarized modes become independent of $\mu$ and $\epsilon$ respectively.