Parametrically Shielding Electromagnetic Fields by Nonlinear Metamaterials

TL;DR

This paper develops an analytical theory showing that nonlinear metamaterials with near-zero refractive index can effectively shield electromagnetic fields at certain frequencies through parametric interactions, with tunable skin depth.

Contribution

It introduces a new theoretical framework for parametric electromagnetic shielding using nonlinear left-handed metamaterials with negative permittivity and permeability.

Findings

Electromagnetic fields can be parametrically shielded by nonlinear metamaterials.

Skin depth can be tuned and made much less than the wavelength.

Shielding occurs even without material absorption due to nonlinear responses.

Abstract

An analytical theory is developed for parametric interactions in metamaterial multilayer structures with simultaneous nonlinear electronic and magnetic responses and with near-zero refractive-index. We demonstrate theoretically that electromagnetic fields of certain frequencies can be parametrically shielded by a nonlinear left-handed material slab, where the permittivity and permeability are both negative. The skin depth is tunable, and even in the absence of material absorption, can be much less than the wavelength of the electromagnetic field being shielded. This exotic behavior is a consequence of the intricate nonlinear response in the left-handed materials and vanishing optical refractive-index at the pump frequency.