Frequency-domain simulations of a negative-index material with embedded gain

TL;DR

This paper models light propagation in negative-index materials with embedded gain, revealing that effective loss compensation depends on the placement of gain materials in regions of maximal field enhancement, with analytical insights into near-field effects.

Contribution

It introduces a frequency-domain model for negative-index materials with nonlinear gain, highlighting the importance of gain placement for loss compensation and providing analytical understanding of near-field enhancement effects.

Findings

Gain materials enable loss compensation only in regions of high field enhancement.

Effective gain is proportional to the average near-field enhancement.

Field enhancement increases in the gain composite and metal inclusions.

Abstract

We solve the equations governing light propagation in a negative-index material with embedded nonlinearly saturable gain material using a frequency-domain model. We show that available gain materials can lead to complete loss compensation only if they are located in the regions where the field enhancement is maximal. We study the increased enhancement of the fields in the gain composite as well as in the metal inclusions and show analytically that the effective gain is determined by the average near-field enhancement.