Modeling the directed transmission and reflection enhancements of the lasing spaser in active metamaterials

TL;DR

This paper demonstrates significant enhancement of reflectance and transmittance in a lasing spaser within active metamaterials, using modeling and numerical analysis to understand the spasing behavior and directed emission.

Contribution

It introduces a model of the spasing metamaterial using an active slab with Lorentz dispersion and analyzes the enhancement and emission properties.

Findings

Reflectance and transmittance exceed 35 dB

Spasing intensity depends non-monotonically on gain

Directed emission of the spasing beam is verified

Abstract

Simultaneously enhanced reflectance and transmittance greater than 35 dB are demonstrated for the lasing spaser (or spasing) behavior in an active fishnet metamaterial. In mimicking a lasing cavity, an equivalent active slab with Lorentz dispersion for the index of refraction is established to model the spasing metamaterial through the Fabry-Perot effect. Numerical and theoretical results show good agreement in the equal enhancement of reflectance and transmittance, as well as the non-monotonic dependence of the spasing intensity on the gain coefficient. In addition, directed emission of the spasing beam is verified numerically.