Tunable random laser based on hybrid plasmonic enhancement

Abstract

This research investigates the hybridized plasmonic response of silver film combined with dispersed silver (Ag) nanowires (NWs) to random laser emission. The mixture of Rhodamine B (RhB) dye and polyvinyl alcohol (PVA) matrix is taken as the gain medium for random lasing, and the silver combination provides feedback mechanisms for light trapping. Importantly, film roughness and the coupling between localized and extended (delocalized) surface plasmons play a vital role in RL performance evaluation. The laser threshold is strongly influenced by film thickness attributed to surface roughness. Furthermore, the variation in film thickness also supports the wavelength modulation of 9 nm (597 nm to 606 nm), which results from the reabsorption of RhB. Additionally, the intriguing capability of emission wavelength tuning under the variation of temperature facilitates exciting prospects for precise wavelength control in plasmonic devices.