Anomalous Lasing Behavior in a Nonlinear Plasmonic Random Laser

TL;DR

This paper reports a novel double-threshold lasing phenomenon in a plasmonic random laser system, driven by strong mode coupling and nonlinear effects of Au nanoislands, with detailed statistical analysis confirming the behavior.

Contribution

It introduces the first observation of double-threshold lasing in a plasmonic random laser, highlighting the role of nonlinear plasmonic nanocavities in lasing dynamics.

Findings

Observation of double-threshold lasing behavior.

Strong coupling of laser modes to plasmonic nanocavities.

Validation of the phenomenon through statistical analysis.

Abstract

An unprecedented double-threshold lasing behavior has been observed in a plasmonic random laser composed of Au nanoislands decorated on vertically standing ZnO nanorods, infiltrated with dye-doped polymer matrix. The strong coupling of random laser modes to plasmonic nanocavities results in a dominant absorption of the random laser emission, leading to the first unusual lasing threshold. At higher pump fluences, the nonlinear optical behavior of the Au nanoislands induces a second lasing threshold. Various statistical tools have been employed to analyze the intensity fluctuations of the random laser modes, validating this unique lasing behavior.