Light scattering in pseudo-passive media with uniformly balanced gain and loss

TL;DR

This paper introduces a new class of metamaterials with balanced gain and loss, resulting in real refractive index and unique scattering properties, bridging passive and active media in photonic applications.

Contribution

It presents the concept of pseudo-passive metamaterials with balanced gain and loss, revealing their transport and scattering characteristics.

Findings

Pseudo-passive media have real refractive index despite gain and loss.

Unbounded pseudo-passive media mimic lossless passive media in transport.

Bounded pseudo-passive samples exhibit unexpected scattering features.

Abstract

We introduce a class of metamaterials with uniformly balanced gain and loss associated with complex permittivity and permeability constants. The refractive index of such a balanced pseudo-passive metamaterial is real. An unbounded uniform pseudo-passive medium has transport characteristics similar to those of its truly passive and lossless counterpart with the same real refractive index. However, bounded pseudo-passive samples show some unexpected scattering features which can be further emphasized by including such elements in a photonic structure.