Lasing From Water Solution of Rhodamine 6G/Gold Nanoparticles: Impact of ${\rm SiO}_{2}$ -Coating on Metal Surface

Gold nanoparticles embedded in an optical gain material, particularly in a water solution of Rhodamine 6G, used in dye lasers can both increase and damp dye flourescence, thus changing the laser output intensity. Simultaneously, such nanoparticles influence the gain material´s resistance against photobleaching. In this paper, we report our study on the impact of the SiO₂ coating of nanoparticles on the enhancement or quenching and photobleaching of the fluorescence. The investigation demonstrates a noticeable improvement of the gain material´s photostability compared to uncoated gold nanoparticles when silicon dioxide coating is implemented.