Light Amplification by Active Meta-mirrors

TL;DR

This paper proposes a scheme using thin films on modulated amplifying materials to achieve significant light amplification via Fano resonances, with potential for enhanced optical control.

Contribution

It introduces a novel meta-interface design that leverages Fano resonances and waveguiding modes for light amplification, supported by analytical and numerical analysis.

Findings

Reflection can be substantially amplified at the meta-interface.

Amplification peaks near Fano waveguiding modes approaching the continuum edge.

Theoretical models and rigorous analysis confirm the amplification mechanism.

Abstract

We consider a scheme of thin films, deposited on periodically modulated amplifying materials. We show that the reflection from such meta-interface can undergo substantial amplification, due to Fano resonances in the thin films. The amplification strongly increases when the Fano waveguiding modes approach the edge of the continuum and degenerate into the leaky surface modes. The study is based on simplified analytical models, as well as on Rigorous Coupled Wave Analysis.