Low-threshold directional plasmon lasing assisted by spatially coherent surface plasmon polaritons

TL;DR

This paper proposes a theoretical method for low-threshold, directional plasmon lasing using spatially coherent surface plasmon polaritons on a meta-surface, effective in near-infrared and visible wavelengths.

Contribution

It introduces a novel approach to achieve low-threshold plasmon lasing with tunable gain requirements on a planar meta-surface, outperforming previous studies.

Findings

Gain coefficients required are significantly lower than previous reports.

Lasing can be achieved at both near-infrared and visible wavelengths.

The method offers a highly efficient, spatially coherent plasmon lasing route.

Abstract

We theoretically propose directional, low-threshold plasmon lasing in both the near-infrared and visible wavelengths by utilizing spatially coherent surface plasmon polaritons on a meta-surface. The gain strength required for threshold lasing can be tuned down to a large extent through compatible structural parameters. Our calculations show that no more than 65 cm$^{-1}$ at 193.5 THz (1.55 $\mu$m) or 267 cm$^{-1}$at 474THz (0.633 $\mu$m) of gain coefficient is sufficient to compensate for the dissipation of metal films for threshold lasing; these values are smaller than any reported studies at the same frequencies. These findings present a planar solid-state route for plasmon lasing that is highly efficient and spatially coherent.